inaf osservatorio astro sico di cataniaweb.ct.astro.it/report/rep2003/report03.pdf · inaf...

INAFOsservatorio Astrofisico

di Catania

Annual Report 2003

June, 30th 2004

INAF - Osservatorio Astrofisico di CataniaCitta UniversitariaVia Santa Sofia 78I-95123 Catania (Ct)Phon +39 095 7332111 / Fax +39 095 330592URL http://woac.ct.astro.it/

“Mario Girolamo Fracastoro” Mountain StationContrada Serra la Nave (Mt. Etna)Ragalna (Ct)Altitude: 1725 m; Longitude: +14o 58.4′; Latitude +37o 41.5′

Phon +39 095 911580

Edited by: G. Catanzaro, M. P. Di Mauro and S. MessinaPrinted: June 30th, 2004Cover: “M. G. Fracastoro” Mountain Station, night view of the 61cm telescope dome

Contents

Foreword xi

Osservatorio Astrofisico di Catania: Staff directory 2003 xiii

1 OACt 2003 Summary/Highlight 1

2 Research 52.1 Solar Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.1.1 Systematic patrol of photospheric and chromospheric activity . . . 52.1.2 Spectroscopic diagnostic and modelling of coronal structures . . . . 62.1.3 Energetic events in the solar atmosphere: flares and eruptive promi-

nences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82.1.4 Emergence and evolution of solar active regions . . . . . . . . . . . 112.1.5 Sunspots rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.1.6 Irradiance variation of the Sun . . . . . . . . . . . . . . . . . . . . . 132.1.7 Internal structure and helioseismology . . . . . . . . . . . . . . . . 152.1.8 Conferences, Meeting and Ph. D. Committes . . . . . . . . . . . . . 16

2.2 Stellar physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172.2.1 Magnetic activity and variability . . . . . . . . . . . . . . . . . . . 17

2.2.1.1 Magnetic structures in the photospheres, chromospheresand coronae of single stars and close binary systems . . . . 17

2.2.1.2 Structure and modelling of the stellar chromospheres andcoronae . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.2.1.3 Orbital period modulation and magnetic activity cycles inclose binaries . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.1.4 Evolution of stellar magnetic activity and related phenomena 242.2.1.5 Systematic observations and activity cycles . . . . . . . . 282.2.1.6 Dynamo theory of stellar magnetic fields . . . . . . . . . . 28

2.2.2 Stellar oscillations and asteroseismology . . . . . . . . . . . . . . . 292.2.2.1 Solar-type stars . . . . . . . . . . . . . . . . . . . . . . . . 302.2.2.2 Asteroseismology of hot subdwarf stars . . . . . . . . . . . 332.2.2.3 Conferences and Meetings Committes . . . . . . . . . . . 33

2.2.3 Chemical composition studies and chemically peculiar stars . . . . . 342.2.3.1 Magnetic Field . . . . . . . . . . . . . . . . . . . . . . . . 342.2.3.2 Chemical Abundances . . . . . . . . . . . . . . . . . . . . 362.2.3.3 Spectrum variability . . . . . . . . . . . . . . . . . . . . . 38

2.2.4 Search for brown dwarfs . . . . . . . . . . . . . . . . . . . . . . . . 42

iii

iv CONTENTS

2.2.5 Nuclear astrophysics . . . . . . . . . . . . . . . . . . . . . . . . . . 422.2.6 Search for extra-solar planets . . . . . . . . . . . . . . . . . . . . . 43

2.2.6.1 Radial velocity exo-planet search . . . . . . . . . . . . . . 432.2.6.2 Modelling stellar magnetic activity for planetary transit

search . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432.3 Extra-galactic Astrophysics and Cosmology . . . . . . . . . . . . . . . . . . 44

2.3.1 Extra-galactic Astrophysics . . . . . . . . . . . . . . . . . . . . . . 442.3.1.1 Observations of BL Lac objects . . . . . . . . . . . . . . . 442.3.1.2 Gamma Ray bursts observation . . . . . . . . . . . . . . . 452.3.1.3 Hot stars in Local Group galaxies . . . . . . . . . . . . . . 45

2.3.2 Cosmology and Large Scale Structure of the Universe . . . . . . . . 462.3.2.1 Formation and Evolution of Substructures and Minihalos. 462.3.2.2 Mechanical heating of the Intergalactic Medium. . . . . . 47

2.3.3 Cosmology and Particle Physics . . . . . . . . . . . . . . . . . . . . 472.4 Laboratory of experimental astronomy and Solar System physics . . . . . . 50

2.4.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502.4.2 Experimental facilities . . . . . . . . . . . . . . . . . . . . . . . . . 51

2.4.2.1 The vacuum chamber . . . . . . . . . . . . . . . . . . . . 512.4.2.2 The ion implanter . . . . . . . . . . . . . . . . . . . . . . 522.4.2.3 Upgrade and calibration of the ion implanter . . . . . . . 532.4.2.4 The UV lamp . . . . . . . . . . . . . . . . . . . . . . . . . 542.4.2.5 Infrared transmittance and reflectance spectroscopy . . . . 552.4.2.6 Raman spectroscopy . . . . . . . . . . . . . . . . . . . . . 552.4.2.7 Photo and ion luminescence . . . . . . . . . . . . . . . . . 55

2.4.3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552.4.3.1 Ion irradiation and UV photolysis of ices . . . . . . . . . . 552.4.3.2 Nitrogen condensation on water ice . . . . . . . . . . . . . 562.4.3.3 C70 fullerene . . . . . . . . . . . . . . . . . . . . . . . . . 572.4.3.4 Carbon and nitrogen implantation on icy surfaces . . . . . 572.4.3.5 Frozen hydrocarbons . . . . . . . . . . . . . . . . . . . . . 572.4.3.6 Evolution of the surface materials on Trans Neptunian Ob-

jects: the role of ion irradiation . . . . . . . . . . . . . . . 582.4.3.7 Understanding the origin of the interstellar 3.4 µm band:

new laboratory striking results . . . . . . . . . . . . . . . 582.4.3.8 Asteroids photometry . . . . . . . . . . . . . . . . . . . . 592.4.3.9 On going research . . . . . . . . . . . . . . . . . . . . . . 60

2.4.4 Workshops and meetings . . . . . . . . . . . . . . . . . . . . . . . . 632.5 Catania astrophysical Observatory Laboratory for Detectors (COLD) . . . 63

2.5.1 Detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642.5.1.1 CCD controllers . . . . . . . . . . . . . . . . . . . . . . . 642.5.1.2 CVD Diamonds detectors . . . . . . . . . . . . . . . . . . 642.5.1.3 SPAD detector . . . . . . . . . . . . . . . . . . . . . . . . 65

2.5.2 Telescopio Nazionale Galileo . . . . . . . . . . . . . . . . . . . . . . 662.5.2.1 Maintenance and upgrade of TNG CCD controllers . . . . 662.5.2.2 Development and maintenance of TNG user interfaces . . 66

2.5.3 Participation in National and international projects . . . . . . . . . 662.5.3.1 Eddington project . . . . . . . . . . . . . . . . . . . . . . 66

CONTENTS v

2.5.3.2 XSHOOTER Spectrograph . . . . . . . . . . . . . . . . . 67

2.5.4 The CCD cameras for Catania Astrophysical Observatory . . . . . 67

2.5.4.1 CCD camera for the Schmidt telescope . . . . . . . . . . . 67

2.5.4.2 CCD camera for the 91 cm telescope . . . . . . . . . . . . 68

2.5.4.3 Support to solar and stellar observations . . . . . . . . . . 68

2.5.4.4 Collaboration with Industries . . . . . . . . . . . . . . . . 68

2.6 Computational technologies for astrophysics . . . . . . . . . . . . . . . . . 69

2.6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

2.6.2 FLY. A parallel tree N-body code for cosmological simulations. APublic Domain code. . . . . . . . . . . . . . . . . . . . . . . . . . . 70

2.6.3 Scientific Visualization . . . . . . . . . . . . . . . . . . . . . . . . . 71

2.6.3.1 Basic Functionalities . . . . . . . . . . . . . . . . . . . . . 71

2.6.3.2 Data Analysis Functionalities . . . . . . . . . . . . . . . . 72

2.6.4 Grid Computing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

2.6.5 Astrocomp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

2.6.6 Future development . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

2.7 The digitation of the archive of astronomical plates of Catania Astrophys-ical Observatory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

3 Projects and Collaborations 77

3.1 National and international projects . . . . . . . . . . . . . . . . . . . . . . 77

3.2 Collaborations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

4 Facilities and Services 83

4.1 Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

4.2 Acquisition of new instrumentation and facilities . . . . . . . . . . . . . . . 83

4.3 Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

4.4 Computing Center and local network . . . . . . . . . . . . . . . . . . . . . 87

4.5 Opto-mechanical workshop and telescopes automation . . . . . . . . . . . . 89

4.5.1 Telescope automation . . . . . . . . . . . . . . . . . . . . . . . . . . 89

4.5.2 Opto-mechanical laboratory . . . . . . . . . . . . . . . . . . . . . . 91

4.6 CCD image acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

4.7 Photometric data acquisition and reduction . . . . . . . . . . . . . . . . . 92

4.8 The ”Mario G. Fracastoro” station on Mt. Etna . . . . . . . . . . . . . 92

4.9 Solar observation facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

5 Out-reach and Education 99

5.1 Out-reach Office . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

5.1.1 Public conferences . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

5.1.2 Visits to the Observatory . . . . . . . . . . . . . . . . . . . . . . . . 101

5.1.3 Special events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

5.2 University Courses and high level Educational Activity . . . . . . . . . . . 106

5.3 Ph.D. Students . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

6 Staff members 109

6.1 Staff on 31 December 2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

vi CONTENTS

List of Publications 1137.1 Refereed papers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

7.1.1 Refereed papers in press . . . . . . . . . . . . . . . . . . . . . . . . 1177.2 Edited volumes (proceedings) . . . . . . . . . . . . . . . . . . . . . . . . . 1177.3 Invited talks and reviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

7.3.1 Invited talks and reviews in press: . . . . . . . . . . . . . . . . . . . 1187.4 Contributions to international conferences . . . . . . . . . . . . . . . . . . 118

7.4.1 Contributions in press . . . . . . . . . . . . . . . . . . . . . . . . . 1247.4.2 Presentations without proceedings . . . . . . . . . . . . . . . . . . . 126

7.5 Electronic publications, short articles and technical reports . . . . . . . . . 126

A Sommario del bilancio OACt 2003 129

List of Tables

1 Catania Astrophysical Observatory, e-mail/phone directory . . . . . . . . . xvi

2.1 Spot parameters obtained from model solutions. . . . . . . . . . . . . . . . 19

4.1 MG Fracastoro station: Telescopes activities . . . . . . . . . . . . . . . . . 95

A.1 Entrate (kEU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129A.2 Spese (kEU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

vii

viii LIST OF TABLES

List of Figures

2.1 Distribution of data and international cooperations involving the solar ob-servations carried out in Catania. . . . . . . . . . . . . . . . . . . . . . . . 6

2.2 Image of the extended solar corona obtained by the LASCO C1 corona-graph on October 30, 1997 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.3 Observations of reconnection phenomena acquired by THEMIS . . . . . . . 10

2.4 A prominence eruption observed by TRACE . . . . . . . . . . . . . . . . . 10

2.5 Reconstruction of evolutionary phases of a recurrent active region (NOAA10050) obtained from the images acquired by THEMIS telescope. . . . . . 11

2.6 Variaton of a sunspot groups angular velocity during the activity cycle. . . 13

2.7 Multi-band best fit to the Total Solar Irradiance (TSI) and the Solar Spec-tral Irradiances (SSI) in the three optical bands. . . . . . . . . . . . . . . . 14

2.8 Helioseismic inversion to probe Newton’s gravitational constant. . . . . . . 16

2.9 Maximum-Entropy-regularized images reconstruction for the componentsof HR1099 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2.10 3D mapping of the photospheric and chromospheric inhomogeneities inHK Lac. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.11 Hβ and Hei D3 chromospheric and TR diagnostics in HD 111456. . . . . . 20

2.12 Plots of interesting portions of the α Cen A HST/STIS and SOHO/SUMERquiet sun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.13 The differential emission measure distribution of α Cen A is compared withcorresponding distributions for the quiet and active Sun. . . . . . . . . . . 22

2.14 log (LX/Lbol) vs. Amax for F-M stars . . . . . . . . . . . . . . . . . . . . . . 23

2.15 Power law fits to the log (LX/Lbol) -Amax relation . . . . . . . . . . . . . . 24

2.16 The expected relative orbital period variation of a star-planet system versusthe orbital period of the planet according to the model by Lanza & Rodono(1999) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.17 Connection between orbital period modulation and magnetic activity inthe prototype eclipsing binary RS CVn. . . . . . . . . . . . . . . . . . . . . 26

2.18 (top panels) Long-term V-band brightness variations of BE Cet (left)) andDX Leo (right). (bottom panel) Seasonal rotation periods vs. time with alinear fit to data. The rotation period monotonically decreases along thestarspot cycle showing a solar-like behaviour for BE Cet (left) and anti-solarfor DX Leo (right). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.19 (left panel) The rotational period variations (∆P) are plotted vs. the meanrotational period. (right panel) The cycle frequency (ωcyc) is plotted vs.the relative surface differential rotation amplitude (∆Ω/Ω). . . . . . . . . . 27

ix

x LIST OF FIGURES

2.20 Li i equivalent width of some PMS candidates plotted as a function of(B − V )0 color index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.21 Evolution tracks identifying η Boo as being in the post-main-sequence phase. 302.22 Evolution tracks identifying η Boo as being in the main-sequence phase. . . 312.23 Radial velocity curve measured for Procyon . . . . . . . . . . . . . . . . . 322.24 Power spectrum of oscillations measured in Procyon . . . . . . . . . . . . . 332.25 Fei lines of HD 180583 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352.26 Effective magnetic field of β Lyrae . . . . . . . . . . . . . . . . . . . . . . . 362.27 FUSE spectrum of HD 207538 modeled . . . . . . . . . . . . . . . . . . . . 372.28 Comparison between the observed and computed Hδ and Hγ lines in HR 6000 382.29 The amplitude spectra for the effective magnetic field strength variation in

γ Equ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392.30 Equivalent width variations of HD 124224 and HD 142990 . . . . . . . . . . 402.31 Fitted spectral regions of the SB2 system HD 191110 . . . . . . . . . . . . 412.32 Radial velocity curve of HD 173524 and composite Hβ profile of HD 216494 412.33 Effects of stellar magnetic activity on planetary transit detection. . . . . . 442.34 Normalized spectra of stars observed in M 33 . . . . . . . . . . . . . . . . . 462.35 Output of the Cineca Key Project simulation at z=2 . . . . . . . . . . . . 472.36 Accretion shock in the Intergalactic Medium around a Dark Matter halo

moving at speed vhalo = 2csound. . . . . . . . . . . . . . . . . . . . . . . . . 482.37 Astrophisycs Laboratory: Apparatus . . . . . . . . . . . . . . . . . . . . . 522.38 Astrophisycs Laboratory: Possible experiments . . . . . . . . . . . . . . . . 532.39 Astrophisycs Laboratory: Upgraded implanter . . . . . . . . . . . . . . . . 542.40 Astrophisycs Laboratory: Photolysis/irradiation of H2O . . . . . . . . . . . 562.41 Astrophisycs Laboratory: Evolution for hydrogenated carbon grains in ISM 592.42 The 5×2 CVD diamond matrix . . . . . . . . . . . . . . . . . . . . . . . . 652.43 The CCD camera for the Schmidt telescope mounted at Cima Ekar . . . . 672.44 The prototype of the CCD camera for the 91 cm telescope . . . . . . . . . 682.45 (left panel) IBM SP 9076. (right panel) IBM p650 Series. . . . . . . . . . . 692.46 Simulation of formation of clusters of galaxies in the universe: user interface 722.47 Simulation of formation of clusters of galaxies in the universe: texture

mapping and ray tracing technique . . . . . . . . . . . . . . . . . . . . . . 732.48 The Astrocomp Portal (http://www.astrocomp.it). . . . . . . . . . . . . . 74

4.1 Library historical section, Agelli (1718) . . . . . . . . . . . . . . . . . . . . 854.2 Library historical section, Newton (1760) . . . . . . . . . . . . . . . . . . . 864.3 The 91-cm Cassegrain reflector with fibre feed interface . . . . . . . . . . . 934.4 Distribution of publications totally or partially based on observations made

at the M. G. Fracastoro station . . . . . . . . . . . . . . . . . . . . . . . . 964.5 Solar facilities: The equatorial spar . . . . . . . . . . . . . . . . . . . . . . 974.6 Solar facilities: Hα a image of the Sun . . . . . . . . . . . . . . . . . . . . 98

5.1 Number of visitors from 1994 to 2003 . . . . . . . . . . . . . . . . . . . . . 106

Foreword

Premessa

Lo scopo di questo rapporto e di presentare i risultati della attivita dell’Osservatorioastrofisico di Catania nel corso dell’anno solare 2003 sul piano scientifico, tecnologico e dipromozione culturale e scientifica nella scuola e nella societa. Esso offre inoltre un utilestrumento di documentazione rivolto alle istituzioni, locali e nazionali, che nell’anno 2003hanno in vario modo sostenuto le attivita dell’Osservatorio o hanno avuto rapporti conesso alle quali va il piu vivo ringraziamento per il supporto ricevuto.

L’Osservatorio Astrofisico di Catania (OACt) fa parte della rete di dodici Osserva-tori dell’Istituto Nazionale di Astrofisica e dispone di due sedi. La principale e ubicataall’interno della Cittadella Universitaria, e comprende gli uffici, la biblioteca, i Laboratoridi ricerca, le officine ottico-meccaniche, e il telescopio per le osservazioni solari. La sec-onda sede, Mario Girolamo Fracastoro, e collocata in localita Serra La Nave sul versantesud-est dell’Etna a quota 1750 m s.l.m. nel comune di Ragalna (CT). Essa e la sedeosservativa dotata di quattro telescopi ed una foresteria.

L’Osservatorio opera in stretta collaborazione con la sezione Astrofisica del Diparti-mento di Fisica e Astronomia dell’Universita di Catania, che ha sede nel suo stesso edificio.Ivi si svolgono le attivita di insegnamento, i corsi per il Dottorato di Ricerca, le attivitaconnesse ai laboratori didattici, e le conferenze.

Foreword

The aim of this report is to present the main results achieved by Catania Astrophysi-cal Observatory during 2003, in the fields of Astronomy and Astrophysics, technologicaldevelopment, and dissemination of the scientific culture in the schools and the society. Itoffers a detailed documentation on all the Observatory’s activities and facilities and it isaddressed, among others, to the Institutions who supported the Observatory during 2003,wich are deeply acknowledged.

The Catania Astrophysical Observatory (OACt) is one of the twelve Observatories ofthe network of the Istituto Nazionale di Astrofisica and it has two separate seats. The mainseat in Catania is inside the Catania University Campus, where research offices, library,laboratories, opto-mechanic workshops, and the solar observing station are located. Thesecond one, dedicated to Mario Girolamo Fracastoro, is a mountain observing station onthe south-west side of Mt. Etna at 1750 m a.s.l. (Ragalna, CT), where four telescopesand a guesthouse are located.

The Catania Astrophysical Observatory strictly co-operates with the Astrophysical

xi

xii FOREWORD

Section of the Physics and Astronomy Department of the Catania University, hosted inthe same building of the Observatory. There university and Ph.D. courses are usually heldtogether with the training laboratory activities for the students and public conferences.

Prof. Santo Catalano(Director)

Osservatorio Astrofisico di Catania:Staff directory 2003

DirectorCatalano Santo

BoardBelvedere G., Cutispoto G., Del Popolo S., Frasca A., Miraglia M., Pagano I., StrazzullaG., Rapisarda M.L., Scuderi S.

Catania Astrophysical Observatory, e-mail/phone directoryName Position e-mail phon ext

@ct.astro.it +39095-7332

ANTONUCCIO Vincenzo Research Astronomer van 318BARATTA Giuseppe Associate Astronomer gbaratta 313, 265BECCIANI Ugo Research Astronomer ube 317, 218BELLASSAI Giancarlo Technical Support gbellassai 303BELLUSO Massimiliano Technical Support mbelluso 279BONANNO Alfio Research Astronomer abo 319BONANNO Giovanni Full Astronomer gbonanno 204, 254BRUNO Pietro Technical Support pbruno 278

BUSA Enza Research Astronomer ebu 261

BUSNE Giuseppe Administration gbu 256

CALI Antonio Technical Support acali 205, 203

CALI Maddalena General Services 250CARBONARO Giuseppe Technical Support gcarbonaro 252, 203CARIPOLI Giuseppe Library gcaripoli 214CARUSO Maria Rita MGF* site Staff 095 911580

continued on next page

xiii

xiv OSSERVATORIO ASTROFISICO DI CATANIA: STAFF DIRECTORY 2003

continued from previous page

Name Position e-mail phon [email protected] +39095-7332

CASTORINA Giovanni General Services 9, 208CATALANO Santo Full Astronomer scat 219CATANZARO Giovanni Research Astronomer gca 223CATINOTO Enrico Technical Support ecatinoto 253CORSARO Gaetano MGF* site Staff scor 095 911580COSENTINO Rosario Research Astronomer rco 260, 259COSTA Alessandro Computer Center alex.costa 273COSTA Pierfrancesco Technical Support pcosta 264CUTISPOTO Giuseppe Associate Astronomer gcutispoto 312DEL POPOLO Santa Administration sdelpopolo 226

segreteria 226DI BENEDETTO Rosario Technical Support sdibenedetto 270DI MAURO Maria Pia Research Astronomer mdm 207DISTEFANO Antonio Technical Support adistefano 200DOMINA Daniela Library ddomina 268FRASCA Antonio Research Astronomer afrasca 240GENTILE Giovanni Technical Support ggentile 201, 203GIUFFRIDA Alfio Computer Center agiuffrida 217,218GRECO Vincenzo Technical Support vgreco 200

LAMPO Rocco Technical Support rlampo 300, 301LANZA Antonino F. Associate Astronomer nlanza 238LANZAFAME Giuseppe Research Astronomer glanzafame 316LEONE Franco Research Astronomer fleone 229LETO Giuseppe Research Astronomer gle 311LO PRESTI Carmelo Administration clopresti 215, 218

MAGAZZU Antonio Associate Astronomer antonioMANGANO Angela Library amangano 248

library 248MARILLI Ettore Associate Astronomer emarilli 246MARTINETTI Eugenio Technical Support emartin 304MASSIMINO Piero Computer Center pmassimino 216, 218MELLINI Maria Administration amministr 225MESSINA Sergio Research Astronomer sme 230MESSINEO Marina Administration mmes 226

MICCICHE Antonio Technical Support ami 209MIRAGLIA Massimo Technical Support mmiraglia 271, 203OCCHIPINTI Giovanni Technical Support goc 305, 203PAGANO Isabella Research Astronomer ipagano 243PALUMBO M. Elisabetta Research Astronomer mepalumbo 242, 265PULEO Giuseppe Technical Support mpuleo 201, 203RAPISARDA Maria Luisa Administration mlrapisarda 224

amministr 224continued on next page

xv



RECUPERO Daniela Library drecupero 247ROMANIA Valentina Administration vromania 262SACCONE Rosaria Administration 227SANTAGATI Luigia Library gsantagati 269SANTOCONO Orazio General Services 9, 208SARDONE Stefano Technical Support ssardone 306, 203SCAFILI Marcella Administration mscafili 263SCIUTO Santo Technical Support ssciuto 233, 232SCUDERI Cosimo MGF* site Staff 095 911580SCUDERI Salvatore Research Astronomer sscuderi 255, 254SPADARO Daniele Associate Astronomer dspadaro 234SPINELLA Franco Technical Support fspinella 314, 265STRAZZULLA Giovanni Full Astronomer gianni 315, 265TERNULLO Maurizio Research Astronomer mternullo 231TIMPANARO M.Cristina Technical Support mctimpanaro 259, 254TRINGALE Gaetana Administration segreteria 228VENTIMIGLIA Agata General Services 9, 208VENTURA Rita Research Astronomer rventura 258WANAUSEK Antonino Technical Support awanausek 302ZINGALE Giuseppe General Services 277

Department of Physics and Astronomy-University of CataniaAstrophysics section

Head of Astrophysics SectionBELVEDERE Gaetano

BELVEDERE Gaetano Associate Professor gbelvedere 236ANASTASI Clelia Administration canastasi 211BLANCO Carlo Associate Professor cblanco 245CATALANO Franco Associate Professor fcatalano 221LANZAFAME Alessandro Researcher acl 239

PATERNO Lucio Full Professor lpaterno 235

RODONO Marcello Full Professor mrodono 220SPAMPINATO Cinzia Administration 210

ZAPPALA Aldo Associate Professor razappala 241ZUCCARELLO Francesca Associate Professor fzucca 237

Ph.D. Students and Fellows

BIAZZO Katia Ph.D. Student kbi 328CIGNA Massimo Fellow mci 244

continued on next page

xvi OSSERVATORIO ASTROFISICO DI CATANIA: STAFF DIRECTORY 2003



COMPARATO Marco Fellow mcoCONTARINO Lidia Postdoc INAF lcont 331DI GIORGIO Salvatore Ph. D. StudentDi STEFANO Elisa Fellow edsFERRO Daniela Fellow dfeLECCIA Silvio Ph. D. StudentPALAZZO Giusimelissa Ph. D. Student gpalROMANO Paolo Postdoc University of Catania prom 329ROMEO Alessio Ph. D. Student

Table 1: Catania Astrophysical Observatory, e-mail/phone directory

* MGF: Mario Girolamo Fracastoro

Chapter 1

OACt 2003 Summary/Highlight

Introduzione al rapporto dell’OACt per l’anno 2003

Le attivita dell’anno 2003 sono state fortemente condizionate dai lavori di ristrut-turazione e recupero dell’ edificio principale della sede di Catania effettuati a cura dell’Universita di Catania. Le operazioni di spostamento e la sistemazione temporanea inlocali insufficienti, legati a tali lavori di ristrutturazione, hanno costretto i ricercatori edil personale tutto a lavorare in condizioni di estremo disagio, per tutto l’anno. Tuttaviale attivita scientifiche sono proseguite con elevato standard ed il personale tutto ha svoltoi propri compiti con impegno e serieta.

L’ Osservatorio di Catania con la stazioni eliofisica e la sede dell’ Etna (Serra La Nave)rimane uno dei pochi osservatori in Italia in cui l’attivita osservativa locale prosegue ad altilivelli di continuita e di qualita con inserimento in programmi nazionali ed internazionali.All’attivita osservativa si affianca una intensa attivita di ricerca nel campo della fisicastellare e solare di riconosciuta valenza nazionale ed internazionale. Presso l’Osservatoriooperano inoltre il laboratorio di astrofisica sperimentale, il laboratorio dei rivelatori perl’astrofisica e il laboratorio di calcolo ad alte prestazioni. L’attivita di ricerca svolta nel2003 si puo suddividere a grandi linee in:

Fisica solare. Le ricerche di fisica solare si sviluppano su linee di tipo osservativo,che utilizzano facilities internazionali da terra e dallo spazio, e di tipo teorico. Esse com-prendono studi di fisica della corona solare, modelli idrodinamici e di riscaldamentodel complesso cromosfera-TR-corona, modelli dinamo con circolazione meridiana, eliosis-mologia e struttura interna. Programmi osservativi sono condotti con i satelliti SOHO,TRACE e con il telescopio THEMIS. Un aspetto rilevante alle osservazioni sistematichedel Sole e dato dall’inserimento nel Global Hα Network organizzato dal Big Bear SolarObservatory e nel programma di ricerca sullo Space Weather attraverso campagne diFlare Warning.

Fisica stellare. Gli studi di fisica stellare presso l’ Osservatorio Astrofisico di Cataniacostituiscono il programma di ricerca piu corposo ed articolato, con una parte prevalentededicata all’ attivita magnetica stellare in stelle singole e doppie, dalla fotosfera allacorona con osservazioni e modelli, oscillazioni stellari e problematiche di struttura stellarecon attivita teorica ed osservativa, composizione chimica e stelle chimicamente peculiari,problemi osservativi di formazione ed evoluzione stellare, processi nucleari di interesseastrofisico.

1

2 CHAPTER 1. OACT 2003 SUMMARY/HIGHLIGHT

Ammassi di galassie cosmologia. Si tratta di un gruppo di piccole dimensioniche si occupa di modellizzazione del plasma intergalattico e dei processi di riscaldamentodi Ammassi di Galassie mediante codici paralleli a N-corpi e codici euleriani a grigliaadattiva, modelli di generazione e propagazione di raggi cosmici di energie estreme instrutture a Grande Scala dell’ Universo.

Laboratorio di Astrofisica Sperimentale. Le ricerche si riferiscono alle interazionitra radiazione e materia in ambienti di interesse astrofisico, con sperimentazione dellemodificazioni chimico-fisiche di bersagli solidi (silicati, materiali carboniosi, gas congelati)bombardati con fasci ionici energetici (3-200 keV) o con fotoni ultravioletti (Lyman-alpha121.6 nm, ovvero 10.2 eV). L’impiantazione di ioni reattivi (H, C, N, O, Na) su silicati ele nuove specie chimiche che si formano nel processo vengono studiate in situ, mediantespettroscopia a riflessione e spettroscopia Raman.

Laboratorio rivelatori per l’ Astronomia. L’ attivita dal gruppo di ricerca sui riv-elatori si articola in due aspetti principali: sviluppo di elettronica e software di controllo dirivelatori CCD, sviluppo e caratterizzazione di rivelatori di nuova generazione. In questoultimo contesto sono da evidenziare lo sviluppo di rivelatore a conteggio di fotoni basatosu ”Intensified CMOS-APS” (IAPS), sviluppo di un sensore a matrice di ”Singlephoton avalanche diodes’ (SPAD) in collaborazione con ST Microelectronics, diCatania, caratterizzazione di un rivelatore a diamante sintetico in collaborazione con ilDipartimento di Astronomia e Scienza dello Spazio dell’Universita di Firenze ed altri is-tituti italiani. Il gruppo e fortemente impegnato nell’upgrade dei sistemi di acquisizionedi immagini nell’ ottico del TNG, e dei telescopi dell’ OAC.

Calcolo ad alte prestazioni e visualizzazione scientifica (HPC). Il sistema dicalcolo parallelo, realizzato tramite il progetto ”Alta formazione nel campo del calcoload alte prestazioni e problematiche astrofisiche attuali” del MURST su finanziamentidell’Unione Europea, ha ricevuto nel 2002 un ulteriore finanziamento che ha consentitonel 2003 l’upgrading del sistema IBM SP3 con un sistema SP4 a 8 processori paralleli,per un totale di 32 processori. Oltre allo sviluppo di codici paralleli nel campo dellasimulazione dell’evoluzione delle galassie il programma prevede lo sviluppo di pacchettidi visualizzazione ed analisi specificamente orientati a dati di simulazioni e di archivio(AstroMD), calcolo e simulazioni su griglia computazionale (GRID) con gestione remotadi simulazioni (AstroComp), orientati verso il Virtual Observatory

L’attivita dell’ Osservatorio nel campo dell’alta formazione anche nel 2003 ha trovatoun notevole impegno, anche con la partecipazione come Socio Ordinario al Consorzio dell’Istituto Superiore di Catania per la Formazione di Eccellenza, con la collaborazione conil Dipartimento di Fisica ed Astronomia nella didattica universitaria (parte di corsi, sup-porto ai corsi di laboratorio, esperienze di osservazioni astronomiche) e di dottorato.Astronomi dell’ Osservatorio sono relatori di tesi di Laurea e tutor di tesi di Dottorato.Purtroppo la mancanza di fondi non ha permesso il rinnovo della convenzione con l’ Uni-versita di Catania per una borsa di studio per il Dottorato di Ricerca.Questo documento descrive le attivita di ricerca e lo sviluppo dell’ Osservatorio Astrofisicodi Catania svolte nel 2003. Considerata la stretta collaborazione con la Sezione Astrofisicadel Dipartimento di Fisica ed Astronomia in questo documento vengono descritte anche leattivita di tale gruppo in una presentazione unitaria come risultato delle sinergie proficuedella integrazione delle due istituzioni nella stessa struttura.

3

OACt 2003 report summary/highlight

All activities in 2003 have been strongly hampered by renewal construction of themain building of the Citta Universitaria. The works have been funded and handled bythe Catania University. The empting operation of the building and temporary settlingon inadequate crowded offices have compelled researchers and all personnel to work in avery comfortless condition, during all the year. However, research activities have beencontinued at high scientific level and all the personnel has afforded its job with highefficiency and awareness of duty.

The Catania Observatory with the eliophysics station and the mountain station onEtna (Serra La Nave) remain one of the few italian astronomical institutions where obser-vation activities are pursued with continuity and at high quality level, within national andinternational collaborations. The observation activities are complemented by theoreticaland data analysis researches in the fields on solar and stellar physics well recognized in thenational and international context. The Catania Observatory include also well equippedlaboratories e.g. the Laboratory for Experimental Astrophysics, the Laboratory of Detec-tors for Astronomy and the High Performance Computing Laboratory. Research activitypursued in 2003 can be grouped within the following main fields:

Solar Physics. Research on solar physics includes observation based activities, whichuse international ground and space facilities, and theoretical researches. All these re-searches relate to physical studies of the solar corona, hydrodynamic models, heatingmechanisms of the chromosphere-Transition Region complex, dynamo models which in-clude meridian circulation, elioseismology and internal structure of the Sun. A relevantaspect of the systematic solar monitoring is the participation into the Global Hα Networkcoordinated by the Big Bear Solar Observatory and into the Space Weather programthrough Flare Warning campaigns.

Stellar Physics. Studies on stellar physics constitute the main body of researchat Catania Astrophysical Observatory . The more relevant part relates to the magneticactivity studies on single and binary stars, from the photosphere to the corona fromobservational and theoretical point of view. Stellar oscillations and internal structure ofstars, chemical composition, chemically peculiar stars, as well as observational aspects offormation and evolution of stars. Problems of nuclear processes of astrophysical interestare also investigated.

Clusters of galaxies and cosmology. This relatively small group recently formed isworking in modelling the intergalactic plasma and on the heating processes of clusters ofgalaxies by means of N-body parallel, numerical codes and eulerian codes with adaptivegrids, as well as on models for the generation and propagation of extremely energeticcosmic rays in large structures of the universe.

Laboratory for Experimental Astrophysics. Researches in this lab refer to theexperiments on the interaction of radiation with iced material in environment of astro-physical interest. Chemical and physical modifications induced on solid targets (silicate,carbon materials, and iced gas) by bombardment with energetic ion beams (3-200 keV)or UV photons (Lyman-α 121,6 nm = 10,2 eV). Implantation of reactve ions (H, C, N, O,Na) on silicates, and the new formed species are studied in situ through diffuse reflection,and Raman spectroscopy.

4 CHAPTER 1. OACT 2003 SUMMARY/HIGHLIGHT

Laboratory of detectors for Astronomy. The activity of the research group isdevoted to two main activities: development of control electronics and software for CCDdetectors, implementation and characterization of new technology detectors. Within thelatter activity it is worth to mention the preparation of photon counting imaging sys-tem based on Intensified CMOS-APS (IAPS), implementation of ”Single PhotonAvalange Diodes” (SPAD) matrix in collaboration with the Catania R&D section ofthe ST Microelectronics, and characterization of a detector based on synthetic diamondin collaboration with the Department of Astronomy and Science of Space of Florence Uni-versity. Furthermore the group is deeply engaged in the improvement and upgrading ofthe image acquisition systems of the Galileo National Telescope (TNG) and of the Cataniatelescopes.

High Performance Computation (HPC) and scientific visualization. The par-allel computing system, implemented within the special project ”Alta formazione nelcampo del calcolo ad alte prestazioni e problematiche astrofisiche attuali” of the MURSTon the base of EU funds, has received further support in 2002, which allowed in 2003the upgrading of IBM SP3 with an additional IBM SP4 system thus having a systemof 32 parallel processors. In addition to parallel numerical codes in the field of galaxiessimulation models, the program is devoted to the development of visualization packagesspecially oriented to archive and simulation data (AstroMD), computation and simula-tion on computational grid (GRID) with remote management (AstroComp) orinted tothe Virtual Observatory

Also in 2003 the Observatory has payed special attention to the high level formationwith the partnerhips in the Consorzio dell’ Istituto Superiore di Catania per la Formazionedi Eccellenza. Collaboration with the Department of Physics and Astronomy of the Cata-nia University for the academic activity, i.e. delivery of university and PhD courses, use ofobservatory labs and telescopes for the experimental and practical exercises. Astronomersof the observatory are currently tutors for the Degree or PhD thesis work. Unfortunately,due to the reduction of funds the special agreement with the Catania University for aPhD fellowship could not be renewed.

The present document is aimed to the description of research activity and developmentof Catania Astrophysical Observatory achieved in 2003. Taking into account the tightcollaboration with the Astrophysic Section of the Department of Physics and Astronomyof the Catania University, activities of both institutions are presented in this documentto stress the positive effects of the unitary scientific policy.

Prof. Santo Catalano(Director)

Chapter 2

Research

2.1 Solar Physics

INAF Researchers: A. Bonanno, M. P. Di Mauro, A. F. Lanza,D. Spadaro, M. Ternullo, R. Ventura

University Researchers: G. Belvedere, A. C. Lanzafame, L. PaternoR. A. Zappala, F. Zuccarello

Postdocs: L. Contarino, P. Romano

Solar physics studies carried out in Catania cover nearly all the regions of the Sun, fromits interior, to the surface and corona. These studies include the traditional systematicpatrol of solar activity, the structure and the dynamics of the solar interior and surface,the theoretical investigation about the generation and evolution of magnetic fields.

Researchers, since several years, are actively involved in some of the most impor-tant space missions devoted to the observations of the solar atmosphere, in particularthe ESA/NASA Solar and Heliospheric Observatory (SOHO) and the NASA TransitionRegion and Coronal Explorer (TRACE). This has allowed the development of activities,among the others, concerning the spectroscopic diagnostics and modelling of coronal mag-netic structures and of the solar wind source regions.

More specifically, research activities have been conducted according to the followingscheme.

2.1.1 Systematic patrol of photospheric and chromospheric ac-tivity

The systematic observations of the Sun in white light and Hα line have been carried on inthe framework of an international collaboration aimed at performing the patrol of solaractivity. The data acquired within this project refer to: sunspots, faculae, quiescent andactive prominences on the disk and on limb, flares. These data are daily sent to thevarious international collecting centers and put on the web page of the Observatory. A”Flare Warning” campaign recently started, within the international research programmeon Space Weather. The campaign is based on the following operations:

5

6 CHAPTER 2. RESEARCH

Figure 2.1: Distribution of data and international cooperations involving the solar obser-vations carried out in Catania.

• observations of active regions appearing on the solar disc, both in the photosphereand chromosphere;

• comparison of the active regions configuration with that observed on the previousday;

• comparison with the magnetograms available on Big Bear Observatory web page;

• singling out active regions which, according to some standard parameters, have thehighest probability to give rise to flares and/or filament eruptions;

• ”warning” e-mail to the national and international scientific community, as well as tothe teams of space experiments involved in the Space Weather research programme.

The final aim is to recognize in advance and to observe by both ground-based and spacetelescopes solar events which are capable of producing troubles in satellite payloads, oreven in Earth-based instruments.

Moreover, Catania Observatory collaborates to the Global High Resolution Hα Net-work and supports the activities of the French-Italian solar telescope Themis.

2.1.2 Spectroscopic diagnostic and modelling of coronal struc-tures

D. Spadaro discussed the principal results obtained by the investigations concerning thephysical structure and the dynamics of coronal magnetic loops, putting into particularevidence the interesting contribution given to these studies by the most recent space

2.1. SOLAR PHYSICS 7

missions [66]. This short review also indicated the principal constraints on the theoreti-cal/numerical models of magnetic loops that arise from these new findings.

D. Spadaro, A. F. Lanza and A. C. Lanzafame, in cooperation with colleagues of theNaval Research Laboratory of Washington, DC and of the NASA Goddard Space FlightCenter of Greenbelt, MD, have investigated the hydrodynamic behavior of coronal loopsundergoing transient heating. This study was stimulated by a wealth of observationalevidence for flows and intensity variations in non-flaring coronal loops, that leads to theconclusion that coronal heating is intrinsically unsteady and concentrated near the chro-mosphere. They carried out 1-D numerical simulations, in which the timescale assumedfor the heating variations (3000 s) is comparable to the coronal radiative cooling time andthe assumed heating location and scale height (10 Mm) are consistent with the valuesderived from TRACE studies. The model loops represent typical active-region loops: 40to 80 Mm in length, reaching peak temperatures up to 6 MK. Spadaro and co-workersused ARGOS, a state-of-the-art numerical code with adaptive mesh refinement, in orderto resolve adequately the dynamic chromospheric-coronal transition region sections of theloop. The new major results from this work are the following. (1) During much of thecooling phase, the loops exhibit densities significantly larger than those predicted by thewell-known loop scaling laws, thus potentially explaining recent TRACE observations ofoverdense loops. (2) Throughout the transient heating interval, downflows appear in thelower transition region (T ∼ 0.1 MK) whose key signature would be persistent, redshiftedUV and EUV line emission, as have long been observed. (3) Strongly unequal heatingin the two legs of the loop drives siphon flows from the more strongly heated footpointto the other end, thus explaining the substantial bulk flows in loops recently observed byCDS and SUMER. The results of these studies have implications for the understandingof the physical origins of coronal heating and related dynamic phenomena [120], [43].

D. Spadaro and R. Ventura investigated the properties of the interface between stream-ers and coronal holes at low heliocentric distances, observing the extended solar coronain the North-West quadrant by UVCS/SOHO. They measured the line profiles of the HiLyα and Ovi resonance doublet and the visible linearly polarized radiance at heliocentricdistances ranging from 1.4 to 2.5 R, and colatitudes spanning from the North pole to theWest equator with steps of ∼ 10 deg. The results show that both the line intensities andthe line widths, in particular those of Ovi, exhibit sharp variations across the streamerboundaries, with a clear anticorrelation between intensities and widths (Fig. 2.2). Thesesteep changes occur in a narrow transition region (5 deg−10 deg), right at the bordersof the streamers, from 1.5 R onwards. The Ovi resonance doublet line ratio steeplyincreases at the edges of the streamer as well, but this occurs at higher heliocentric dis-tances (above 2 R). Hence the marked broadening of the Oiv lines and the considerablerise of their intensity ratio just outside of the borders are an evident signature of thetransition from closed to open field lines in streamer magnetic field topologies. This be-haviour also implies that a strong and preferential non-thermal heating of Oiv ions inthe direction coinciding with the line of sight and the turn-on of a significant outflowoccur in the open magnetic field region near or just outside of the streamer edges. Suchconclusion may have important consequences for realistic theoretical models of streamersand the source regions of the slow solar wind. Paper submitted to A&A at the end of 2003.

R. Ventura and D. Spadaro compared the physical properties of the extended solarcorona inside streamers with those deduced for interstreamer regions, also considering the


possible dependence of such differences on the phase of the solar activity cycle (study isin progress).

2.1.3 Energetic events in the solar atmosphere: flares and erup-tive prominences

Solar flares are complex phenomena, characterized by a sudden and localized energy re-lease (1029 − 1032 erg), which produces emission of electromagnetic radiation, heat flow,bulk plasma motions, particle acceleration. Moreover, the observations have put in evi-dence that the primary energy release takes place in corona and subsequently involves theunderlying layers of the solar atmosphere (Priest & Forbes, A&A Rev., 10, 313, 2002).Therefore the study of flares from the observational point of view must be carried oncomparing data acquired in various spectral ranges, in order to have information on thephysical processes occurring in different atmospheric layers. The results obtained fromthese studies seem to confirm the hypothesis that one of the physical processes at the baseof flares is the magnetic reconnection, caused by breaking and successive merging of mag-netic field lines. However, further observations are necessary to improve our knowledgeabout the role of some phenomena during these events (mechanisms of energy transportduring the first phases of reconnection, chromospheric plasma evaporation in post-flareloops, role of shock waves in heating the plasma, etc.).It is also worth noting that more energetic flares (classes M and X), if associated with

Coronal Mass Ejections (CME) directed towards the Earth, can have remarkable conse-quences on Space Weather and give rise to a series of phenomena that can interfere withsome human activities (systems of radio communications, GPS positioning systems, elec-trical distribution networks, etc), so that, in a society more and more based on electronicsystems, it becomes extremely important to be able to forecast such events in sufficienttimes in order to take the due precautions.In this framework, Contarino, Romano, Ternullo and Zuccarello, considered two mainaspects of the subject of rapidly evolving events: the study of the characteristics that agroup of spots must have in order to produce flares of classes X or M, and a more specificstudy on physical mechanisms at the base of solar flares.The first aspect has been treated by means of a statistical analysis, based both on data inthe visible range, some acquired at Catania Astrophysical Observatory (OACT), othersprovided by NOAA, and on data in the X-ray range provided by GOES satellite, to de-termine what are the conditions which characterize active regions hosting M and X flares([127]; [121]; Ternullo et al.,in progess). This analysis, together with an observationalcampaign carried out at OACT, allowed these researchers to set a Flare Warning system.For the second aspect, Zuccarello, Contarino and Romano, in cooperation with E. Priest

(St. Andrews University, Scotland), have studied the flare activity occurred in activeregion NOAA 8421 using EUV (1600 and 171 A) and WL images acquired by TRACEtelescope, Hα BBSO images, Mitaka magnetograms and YOHKOH hard X-ray data. Theresults obtained from this analysis confirmed that: i) flares triggered by a process of mag-netic reconnection can be caused by the interaction between the magnetic field lines of acoronal arcade and a new magnetic flux tube emerging from the subphotospheric regions;ii) reconnection can occur in the loops of an arcade at gradually increasing heights as afilament rises towards the more external layers; iii) a process of chromospheric evaporationcan be at the base of an increase of brightness in moss surrounding the footpoints of an


Figure 2.2: Image of the extended solar corona obtained by the LASCO C1 coronagraphon board SOHO on October 30, 1997, through a narrow-band Fabry-Perot filter at thecentre of the ionFexiv 5303 A line. Superposed on the LASCO image are the UVCS slitfields of view (white lines) at nominal slit height of 1.75 R, for P.A.=330 deg (a) andP.A.= 270 deg (b). The nominal heliocentric distance and P.A. for each slit refer to thedistance and P.A. of the point along the slit that is closest to the limb (shown as a whitedot). The Lyα and Oiv 1032 A total line intensities and 1/e half-widths, as well as theOiv line ratios, vs. position angle along slit (a) and (b) are shown at the bottom of thefigure.


arcade [128].In another event two distinguished reconnection phenomena have been observed: theformer in the low solar atmosphere, near a structure called cancelling magnetic feature(CMF) (see fig. 2.3), that caused the destabilization of a filament and the successiveeruption of part of it, and the latter in corona, caused by the passage of the filament([17],[87]). Such events provide the opportunity to verify the model of reconnection in thelow solar atmosphere, proposed by Livitnenko (ApJ, 515, 435, 1999).As far as the prominence activation is concerned, many authors have put in evidence,both on theoretical and observational basis, the fundamental role carried out by the he-licoidal configuration of the magnetic field in the prominence instability. In this context,Romano, Contarino and Zuccarello, have studied an event occurred in AR 9077 (see fig.2.4), approximating the prominence to a curved cylindrical flux tube and measuring the

Figure 2.3: Sequence of blue-shifted (left column), Hα center (center column) and redshifted (right column) images acquired by THEMIS at (a) 17:13 UT, (b) 17:34 UT. Thewhite arrow in the central image indicates the CMF. North is on the top, west on theright (f.o.v. 24500× 24500 km2).

Figure 2.4: 171 A image taken by TRACE at 23:29 UT during a prominence eruption.The bright helical structures in the prominence legs are clearly visible. North is on theleft, west on the top.


helicoidal twist of the magnetic field lines using 171 A images acquired by TRACE.They have estimated the critical twist value at which the eruption takes place and haveobserved a decrease of the total torsion of the field with time.

Moreover, using magnetograms of AR 8375 acquired by MDI/SOHO, they have esti-

Figure 2.5: Reconstruction of NOAA 10050 obtained from the images acquired byTHEMIS telescope in the centre of the Hα line on July 27, 2002. The field of view is∼ 35000× 35000 km2. North is on the top, west on the left.

mated the magnetic helicity transport in corona, related to the emergence of new fluxtubes and to their horizontal motion at photospheric level. Such analysis allowed themto confirm the important role played by helicity in prominence destabilization, and tocharacterize in the emergence of the already twisted magnetic field, the more efficientmechanism for the attainment of an unstable configuration ([41]; [42]; [116]).

2.1.4 Emergence and evolution of solar active regions

The detailed study of the configuration and distribution of emerging magnetic flux inthe solar atmosphere during the formation of active regions plays an important role inorder to obtain information on the origin and the emergence of magnetic flux tubes, withimplications for the understanding of the phenomena at the base of the solar dynamo.In particular, the formation of active regions (AR) on the Sun is a consequence of thephenomena of magnetic buoyancy that take place in the layers below the photosphere andthat subsequently involve the external layers of the solar atmosphere. Thanks to severalobservations, nowadays it is possible to give a detailed picture of the phenomena that areobserved during the first evolutionary phases of an AR (see van Driel-Gesztelyi, L., IAUColloquium 188, ESA SP-505, 113, 2002, for a review): plasma motions, formation ofpores, appearance of loop structures, (called Arch Filament System or AFS), phenomenaof coalescence of pores, etc. Despite that, it is not yet possible to establish, during thefirst evolutionary phases of an AR, if it will have a complete evolution (with an average


lifetime of 1 - 2 months), or if it diffuses after short time (1-4 days).

In this framework, using data acquired during an observational campaign carried outat the THEMIS telescope in IPM mode, coordinated with other instruments (OACT,TRACE, EIT/SOHO, MDI/SOHO), Spadaro, Billotta, Contarino, Romano and Zuc-carello, have analyzed the first evolutionary phases of a recurrent active region (NOAA10050), in order to study the morphology and dynamics of its magnetic structures duringtheir emergence and early development (see fig. 2.5). The main result obtained from thisanalysis concerns the dynamic evolution of the AFS crossing the polarity inversion line:the line of sight velocities determined from Doppler measurements, confirm that the loopsforming the AFS show an upward motion at their tops and a downward motion at theirextremities, but also indicate that the upward motion decreases while the active regiondevelops. Moreover, these authors have found that, within the limits of the temporalcadence and spatial resolution of the instruments used, the first evidences of the activeregion formation are initially observed in the transition region and lower corona and lateron (i.e. after about 6 hours) in the inner layers (chromosphere and photosphere). An-other interesting result concerns the analysis of the magnetograms, indicating that theinitial increase of the magnetic flux seems to be nearly simultaneus with the active regionappearance in the transition region and lower corona and that the rate of increase of themagnetic flux during the active region formation is not constant, but it is steeper at thebeginning (i.e. during the first 150 hours) than in the following period. All these resultsmay indicate the presence of some mechanism which decelerates the magnetic flux emer-gence as more and more flux tubes rise towards higher atmospheric levels. Finally, theseauthors have stressed the observed asymmetries between the preceding and the follow-ing sides of NOAA 10050 (the p-side is more extended than the f-side; the p-side movesforward from the initial outbreak position much faster than the f-side recedes; the AFSf-side exhibits higher plasma velocities than the p-side) (Spadaro et al. in progress).

2.1.5 Sunspots rotation

At atmospheric levels, the solar angular velocity pattern may be described by the em-pirical law: Ω(θ) = a + bsin2θ (Ω is the angular velocity, θ is the latitude, a and b areparameters deduced from the data best fit). However, it has been shown that the Ω(θ)values depend on several factors: i) the layer where the observations are made; ii) thechoice of a magnetic tracer or field-free plasma; iii) the tracer used (sunspots, faculae,supergranules, giant cells, coronal holes, bright points); iv) the evolutionary stage of thetracer; v) the tracer lifetime; vi) the phase of the solar cycle.As far as point vi) is concerned, it has been shown that during minima the angular ve-locity appears to be higher than during the other phases of the cycle.In this context, Zappala and Zuccarello used the ”age selection methodology” (ASM) tostudy the variability of the sunspot groups angular velocity during the activity cycle. TheASM is able to separate the contribution of Young Sunspot Groups (YSG) from that ofRecurrent ones (RSG) in the angular velocity determination and therefore to evaluatewhether the increase in angular velocity during minima (reported in literature using allsunspot groups (ASG) as tracers), is due to a greater statistical weight of YSG on RSGor whether it reflects a global characteristic of the Sun. The results obtained from theanalysis of sunspot groups data collected during the period 1874-1981 (Greenwich Photo-


heliographic Results) indicate that during minima, besides the fact that the percentage ofRSG drops to ≤ 5%, both YSG and RSG show the same increase in angular velocity, i.e.0.16 degrees/day (see fig. 2.6). Comparing these results with those reported in literatureand taking into account the internal angular velocity as deduced by p-mode oscillations, itis possible to conclude that the observed higher angular velocity during minima concernsseveral layers of the Sun ([48]; [128]).

Figure 2.6: Superposition of the annual average sunspot-groups rotation rates, accordingto their year nearest to the sunspot minimum (indicated by 0), each year weighted ac-cording to the number of velocity values. The superposed rotational rate residuals arereported separately for ASG (top), YSG (middle) and RSG (bottom). The bars indicatethe standard deviations.

2.1.6 Irradiance variation of the Sun

Lanza, Rodono and Pagano, in collaboration with P. Barge and A. Llebaria of the Lab-oratoire d’Astrophysique de Marseille, analysed the time variability of the total solarirradiance (TSI) as measured by the VIRGO experiment on board the satellite SoHO inorder to model the variability of the Sun as a star. Apart from the phases near the mini-mum at the beginning of the activity cycle 23, the period of the rotational modulation issignificantly different from the solar synodic period as a consequence of the growth anddecay of active regions on time scales shorter than a solar rotation. In order to modelthe variability of the TSI, they considered the contributions of discrete active regions anda uniformly distributed background emission. Specifically, to reproduce the rotationalmodulation of the TSI, they used three active regions, the areas and coordinates of whichwere changed every seven days to account for their evolution. The simultaneous presenceof dark spots and bright faculae was considered by means of appropriate contrast func-tions which took into account the observed center-to-limb dependence of their contrast


Figure 2.7: Upper panels: The simultaneous multi-band best fit to the Total Solar Irra-diance (TSI) and the Solar Spectral Irradiances (SSI) in the three optical bands centeredat the wavelengths of 402, 500 and 862 nm, obtained with the stellar-like model of Lanza,Rodono and Pagano, in panels (a), (c), (e) and (g), respectively. The time interval anal-ysed is close to the maximum of solar activity cycle 23. Lower panels: The residuals of thebest fits in each passband plotted in the corresponding upper panel, respectively (panels(b), (d), (f), (h)).

with respect to the unperturbed photosphere. The method proved to be capable of mod-elling the variability of the TSI on time scales going from 7 − 10 days up to the solarcycle. The relative amplitude of the residuals was of the order of (1 − 2) × 10−4 withthe larger values observed during the phases of maximum solar activity of cycle 23. Theapplication of a similar technique to solar-like stars, such as those that will be observedby the next generation of space-borne photometers (e.g., COROT and Kepler), shouldallow us to minimize the effects of stellar magnetic activity on the detection of planetarytransits. Moreover, the availability of long-term highly accurate light curves will allow usto measure stellar rotation period, detect stellar activity cycles, and derive informationon the inclination of the stellar rotation axis. The location of the active regions and theirirradiance properties can also be retrieved with moderate accuracy from single-band lightcurves. However, a combination of multi-band photometry and spectroscopy will allow usto constrain some of the free parameters of the model and improve the mapping of stellarsurfaces.

Lanza, Rodono and Pagano are presently extending their approach to model the simul-taneous observations of the Total and Spectral Solar Irradiance (SSI) variations as moni-tored by the detectors of the VIRGO experiment on board of SoHO. The SSI narrow-banddata should allow to derive information on the spot and facular contrasts as a functionof the wavelength allowing an estimate of their effective temperatures, at least when onestable active region dominates the rotational modulation. A preliminary example of asimultaneous multi-band fit with three active regions is shown in Fig. 2.7.


D. Spadaro, within a talk on the influence of solar irradiance on the terrestrial climate,discussed the relationship between the variations of irradiance, due the a different levelof solar magnetic activity or to perturbations in the orbit of the Earth around the Sun,and the behaviour of the temperature on the surface of our planet, also comparing theseeffects with those produced by the increase in the human industrial activities occurred inthe last century [65].

2.1.7 Internal structure and helioseismology

Helioseismology has played a formidable role for the detailed comprehension of the struc-ture and dynamics of the Sun, leading to the solution of the neutrino problem, andcontributing to achieve a sensible improvement in the description of physical processesthat govern the behaviour of matter and radiation in stellar interiors.

M. P. Di Mauro, R. Ventura and L. Paterno, which for several years have been involvedin closely related activities, with long history of collaboration on helioseismology, haveproduced several reviews on this subject.

The helioseismic approach and what it has been learnt about the interior of the Sunduring the last decades have been extensively reviewed by M. P. Di Mauro [62]. Thisreview, after an introductory history, recalls the basic physics and the methodologies of the“global” helioseismology, based on analysis of normal mode frequencies, to reveal radialand latitudinal variations of the global properties of the solar structure and dynamics ofthe Sun.

M. P. Di Mauro and L. Paterno, presented [63] the current status of helioseismicstudies and commented the perspectives for future investigations by even more precisehelioseismic observations from ground and space and development of new techniques ofanalysis to reconstruct the complete picture of the Sun and solve the most discussed openquestions in solar physics.

In [64], L. Paterno, M. P. Di Mauro and R. Ventura recall the basic physics of stellarpulsations and how these can be used to infer the structural and dynamical properties ofthe Sun and the stars, pointing out how the successes of helioseismology have producedsignificant improvements in the description of stellar evolution, opening the doors to itsdaughter discipline: the asteroseismology.

An important goal of helioseismology is to provide information about the basic physicsand parameters which determine the structure of the solar interior. Recently, M.P. DiMauro in collaboration with Christensen-Dalsgaard of the University of Aarhus and withH. Schlattl and A. Weiss of the Max Plank Institute of Garching has worked on theextension of the use of the tools of helioseismic inversions to provide significant constraintson physical fundamental parameters, such as, e.g., the value of Newton’s gravitationalconstant G. The authors found that the effects of changes to G are small compared with,and cannot in any obvious way be separated from, effects of other uncertainties in theassumed physics of the solar interior, such as nuclear reaction parameters or opacities.They concluded that the solar calibration and the present solar model are clearly notaccurate enough to allow a determination of G better than laboratory experiments cando. Figure 2.8 shows the inversion results for the sound speed obtained with the the useof models with different G′ = G. It is shown that with the present uncertainty with whichoscillation frequencies are measured, helioseismic inversions cannot allow to distinguishbetween similar models which differ only by 0.1% in the value of G′. Moreover, the sound-


Figure 2.8: The relative squared sound-speed difference between the Sun and solar mod-els, in the sense (Sun)–(model), as inversion of the set of data obtained in 1996 by theSOI/MDI instrument on board the SOHO satellite with modes l < 100. The black dotsare obtained for a standard solar model with G0 = 6.6723×10−8 and M = 1.9891×1033.The grey dots are obtained for a model with G′ = 0.999G0 and the asterisk for themodel with the value of G′ = 1.0065G0, with corresponding values of M ′ such thatG′M ′ = (GM) = G0M. The vertical error bars correspond to the standard deviationsbased on the errors in the mode sets, whereas the horizontal bars give a measure of thelocalization of the solution.

speed inversion results for the extreme case of a model with an higher G′, increased by0.65%, visibly deviates in the region with 0.1 ≤ r/R ≤ 0.3 from the standard case,and the difference between the model and the Sun increases in magnitude by about 30%(study is in progress).

During the year 2003, M. P. Di Mauro has established a new collaboration with D.Cardini and I. Mazzitelli of the IAS, CNR Tor Vergata (Rome) on the use of helioseis-mology and the comparison of the theoretical oscillation frequencies with the observedones, in order to constrain solar models, produced with the FRANEC stellar evolutioncode, and characterized by the introduction of Canuto and Mazzitelli (1992) convectionformulation.

2.1.8 Conferences, Meeting and Ph. D. Committes

• D. Spadaro, together with E. Antonucci (INAF-OATo) and B. Caccin (Univ. ofRome, Tor Vergata), organized and directed the workshop ”New Prospects for SpaceObservations of the Dynamics of the Sun”, held at the International School of SpaceScience of L’Aquila from September 1 to 6, 2003. The workshop reviewed the currentscientific understanding and focused on the outstanding questions concerning the

2.2. STELLAR PHYSICS 17

principal aspects of the dynamics of the Sun, in order to identify and plan the spe-cific observational strategies and related analysis which are required to improve ourknowledge of these aspects. About 50 persons, including several graduate students,attended the workshop.

• M. P. Di Mauro was a member of the Scientific Organizing Committee of the JD12 “Solar and Solar-like oscillations: insights & challenges for the Sun and Stars”,IAU XXV General Assembly , July 18-19, 2003, Sydney (Australia). This jointdiscussion covered the subject of ‘solar-like’ oscillations, i.e. those that are excitedstochastically by convection and occur in the Sun and in solar-type stars. The ses-sion concerning Helioseismology treated the following topics: sub-surface structuresand flows revealed by local-area, acoustic tomography, and holography, convectionzone, tachocline and core structure, variations with the activity cycle, low-degreehelioseismology and implications for asteroseismology.

• D. Spadaro was appointed by the Department of Pure Mathematics and Mathemati-cal Statistics of the University of Cambridge (UK) as external examiner of a studentcandidate for the Ph.D. degree. The oral examination took place in Cambridge, onthe 16th December 2003.

2.2 Stellar physics

2.2.1 Magnetic activity and variability

INAF Researchers: I. Busa, S. Catalano, G. Cutispoto, A. Frasca, A. F. LanzaG. Leto, E. Marilli, S. Messina, I. Pagano

University Researchers: G. Belvedere, A. C. Lanzafame, M. RodonoIRA Researchers: C. Buemi, P. Leto, C. Trigilio, G. UmanaPhD Students: K. BiazzoFellow: G. Marino

2.2.1.1 Magnetic structures in the photospheres, chromospheres and coronaeof single stars and close binary systems

Mapping of the atmospheric inhomogeneities of HR 1099. For the RS CVn binary starHR 1099 (V711 Tau) Messina, Lanza and Rodono have continued the multiwavelengthstudy begun in 2002 in collaboration with researchers from Armagh Observatory. Therotational modulation of EW of selected spectroscopic lines obtained during the MUSI-COS98 campaign, along with photometric light curves, and a study on the correlationbetween optical and X-ray flares were presented in a first paper [26]. In a second paper[27] Doppler Images of HR 1099 derived from spectra taken during the same campaign andconstrained by contemporaneous APT photometry were presented. The resulting max-imum entropy reconstructions based on the least-squares deconvolved profiles, derivedfrom ∼2000 photospheric absorption lines, reveal the presence of starspots at medium-high latitudes (Fig. 2.9). Maps for both components of the binary system have beenobtained for the first time. The predominant structure in the primary component is an


off-centered polar spot. The images obtained for the secondary component show a lowlatitude spot around orbital phase 0.7. This spot seems to mirror the structure seen onthe primary. It might suggest that tidal forces may influence the spot distribution on thisbinary system.

Figure 2.9: Maximum-Entropy-regularized images reconstruction for theprimary component (K1 IV) of the HR1099 system (upper panel) and forthe secondary component (G5 V) (lower panel). The right-hand panelsindicate the fractional spot occupancy as a function of latitude.

Measurement of starspot temperatures. The study of the average photospheric tem-perature variation based on the line-depth ratios (LDR) has been continued by Catalano,Frasca, Marilli and Biazzo. Model of rotational variation of the average surface temper-ature with amplitudes of 177 K, 119 K, and 127 K for VY Ari, IM Peg and HK Lac,and of the contemporaneous light curves are in progress to search for a unique solution ofthe spot parameters, relative area and temperature. Preliminary results of a spot-modelsimultaneously applied to the light curves and temperature curves have been presented[94] and their main results are summarized in Table 2.1. Moreover they have shown thatchromospheric emission, measured as excess emission in the Hα line is anticorrelated withthe temperature curve, as expected from the solar analogy of spot and plage association[94] and we have proposed a rough 3D mapping of the photospheric and chromosphericinhomogeneities in VY Ari, IM Peg and HK Lac (see e.g. Fig. 2.10).

New average photospheric temperature data are being obtained and analyzed for theactive binaries HR 7275 and λ And and for some young single stars (k1 Cet, HD 166,ε Eri, χ1 Ori). Main sequence stars show both smaller light and temperature variation


Figure 2.10: Left panel: Temperature and Hα modulation curves of HK Lac (dots) withthe computed solution (full line). Right panel: Schematic representation of the photo-spheric spots (dark area) and chromospheric plages (bright area).

indicating a smaller spot coverage with respect to the very active RS CVn binaries.

Spatial association of spots and plages. The study of spatial association of spots andplages in active binary systems has been continued by Catalano, Frasca and Marilli bymeans of contemporaneous spectroscopic Hα and photometric observations. Spectroscopicobservations were carried out with the REOSC spectrograph at Catania AstrophysicalObservatory in the spectral range 5860–6700 A, while photometric have been obtained invarious collaborations.

The results of spectroscopic observations of the active eclipsing binary ER Vul in the5860-6700 spectral range carried out at the Catania Astrophysical Observatory have beenpresented [10]. All spectra display chromospheric emission which fills in the Hα absorptionlines of both components. The equivalent width (EW) of the Hα emission measured bysubtraction of a synthetic spectrum built up with spectra of inactive standard stars, arisenfrom both components, shows a phase-dependent variation. It reaches its maximum value

Table 2.1: Spot parameters obtained from model solutions.Parameter VY Ari IM Peg HK Lac

Tsp/Tph 0.80 0.84 0.755Tsp(K) 3933 3919 3598∆T (K) 983 746 1168Aarel 0.150 0.093 0.148

a Total relative area in units of the star surface.


Figure 2.11: Hβ and Hei D3 chromospheric and TR diagnostics in HD 111456, not usualin mid F-type stars.

just before the primary eclipse. The secondary, cooler component was found to be themost active and its Hα residual emission shows the same trend as the total Hα emission,along the orbital phase. An apparent decrease of the Hα EW around the ingress phase ofthe primary eclipse is interpreted in term of prominence-like structures. ¿From accuratemeasurements of radial velocities by using the cross-correlation technique, a new orbitalsolution has been derived.

Spectroscopic and photometric observations of the young F5-6 V field star HD 111456which exhibits emission cores in the Caii H and K lines and a filling in the Hα linehave been performed to characterize this active star [57]. Although the limit of magneticactivity detectability at optical wavelengths occurs around F5-6 spectral types, HD 111456shows unusual chromospheric and TR activity, as confirmed by the high UV fluxes in theCii, Civ, Siii and Siiv lines and by our detection of excess Hα and Hβ emission and HeiD3 absorption (Fig. 2.11).

The Caii and Hα chromospheric emission fluxes do not show any detectable variationon time scales of few days, as well as uvby photometry. A possible explanation in termsof a very high level of magnetic activity and a homogeneous distribution of active regions,both at chromospheric and photospheric level, or a very low inclination of the rotationaxis with respect to the line of sight is proposed. From 1998 to 2001 the radial velocityshows clear variations indicating a possible binary system, not confirmed by the spectralenergy distribution.

Short and long term chromospheric activity in the triple system DH Leo has been alsoinvestigated [95]. Enhanced chromospheric emission has been detected on both compo-nents of the inner close binary, whereas the slowly rotating tertiary was found to be afairly inactive K5 dwarf.


Figure 2.12: Plots of interesting portions of the α Cen A HST/STIS and SOHO/SUMERquiet sun, coronal hole and solar spot spectra, shifted of −25, −35, and +50 in units ofthe y-axis, respectively (except for the bottom-left panel where the solar spot spectrumis shifted of +20 units). The line identified in the α Cen A STIS spectrum are labelled,while those identified on the Sun by Curdt et al. 2001 (A&A 375, 591) are marked withvertical lines above the quiet Sun spectrum.

2.2.1.2 Structure and modelling of the stellar chromospheres and coronae

Pagano, in collaboration with J. Linsky and Duncan at University of Colorado and othercolleagues has completed the analysis of a high resolution echelle spectra of α Centauri A(G2 V) acquired by the STIS spectrograph on board of the Hubble Space Telescope[59]. They obtained an atlas of 671 emission lines representing 37 different ions and themolecules CO and H2 in the spectral range 114–167 nm, measured with a resolution of 2.6km s−1, an absolute flux calibration accurate to±5%, and an absolute wavelength accuracyof 0.6–1.3 km s−1 [157]. In Figure 2.12 we plot interesting regions of the α Cen A spectrum,and the SUMER spectra of a coronal hole, a sunspot, and the quiet Sun, respectively.Pagano et al. intercompare the redshifts, nonthermal line widths, and parameters of twoGaussian representations of transition region lines (e.g., Si IV, C IV), infer the electrondensity from the O IV intersystem lines, and compare their differential emission measuredistributions (see Figure 2.13). The main purpose of this study was to determine howthe atmosphere and heating processes in α Cen A differ from the Sun as a result of thesmall differences in gravity, age, and chemical composition of the two stars [102]. Anotherpurpose of this study was to provided an excellent high resolution UV spectrum of a solar-like star that can serve as a proxy for the Sun observed as a point source when comparingother stars to the Sun.

Spatial association of spots and X-ray coronal emission. Messina, Rodono et al. haveinvestigated the correlation between the light curve amplitude and the level of coronalX-ray emission from single lower main-sequence stars [38]. The maximum amplitude(Amax) of spot-induced brightness variations from long-term V-band photometry and the


Figure 2.13: The differential emission measure distribution of α Cen A (solid thick line)is compared with corresponding distributions for the quiet Sun and active Sun. Theintersystem lines of O III 1666 A, and of the O IV UV 0.01 multiplet near 1400 A matchthe differential emission measure distribution for electron density of logNe=9.5–10 [cm−3].The Chandra X-ray data are from Raassen et al. 2003 (A&A 400, 671).

ratio (LX/Lbol) between X-ray and bolometric luminosities are suitable indicators of thelevel of magnetic activity in the photosphere and in the corona. By using these activityindicators Messina et al. have found that the upper envelope of Amax and the level ofX-ray emission increase monotonically with decreasing rotational period (P) and Rossbynumber (R0). Amax shows a break around 1.1 d that separates two rotation regimeswhere the starspot activity shows different behaviours, X-ray emission shows evidenceof super-saturation among the fastest rotating stars (P≤ 0.3 d). The highest values ofAmax and X-ray emission are found among K-type stars. Finally, the activity parametersLX/Lbol and Amax are found to be correlated with each other (Fig. 2.14), thus confirmingthe dependence of coronal activity on photospheric magnetic fields. More precisely, theLX/Lbol-Amax distribution shows the presence of an upper envelope, which is constant atthe LX/Lbol' −3.0 saturation level, and of a lower envelope. The best fit to the lowerenvelope is given by a power law with steepness decreasing from F-G to M spectral types.Such spectral-type dependence may be related to a colour dependence of Amax on the totalstarspot filling factor, as well as to the coronal emission being possibly more sensitive tostarspot activity variations in F- and G-type than in M-type stars. The LX/Lbol-Amax

mean values for each cluster in our sample decrease monotonically with increasing age,showing that the levels of photospheric and coronal activity evolve in time according toa single power law till the Sun’s age (Fig. 2.15).

2.2.1.3 Orbital period modulation and magnetic activity cycles in close bi-naries

Rodono and Lanza reviewed for the Proceedings of the IAU Symposium 219 the connectionbetween orbital period variation and magnetic activity in close binaries with late-typecomponents. They discussed recent observational studies of Algols, RS CVn’s, W UMa’sand CVs in the framework of theoretical models based on the Applegate’s mechanism


F5-F9 G0-G7

G8-K5 K6-M4

Figure 2.14: log (LX/Lbol) vs. Amax for F-M stars (from top left to bottomright panel). Circled symbols (and also open triangles for M-type stars)and open diamonds represent the fast and ultra fast stars, respectively,in the Amax-P upper envelope. Open squares represent the stars in thesuper-saturation regime (P≤ 0.3 d). Continuous and dotted lines arethe power law fits to the lower and upper envelope data, respectively.Capital letters (A, B, C and D) indicate the stars appreciably below thelower envelope.

to interpret the observed orbital period modulation in terms of cyclic changes of thegravitational quadrupole moment induced by a magnetic activity cycle affecting one ofthe binary components. In the light of such an approach, the study of orbital periodmodulations offers a promising tool to investigate hydromagnetic dynamos operating inthe interior of active stars, in particular, to address the fundamental question of theinteraction between rotation and magnetic fields in non-linear dynamo regimes. Moreover,


Figure 2.15: Power law fits to the log (LX/Lbol) -Amax relation. Different line-stylesand symbols are used to distinguish different spectral ranges and clusters, respec-tively. The different symbols represent the mean log LX/Lbol for each cluster, com-puted using the values plotted in Fig. 2.14 for P≥1.1 d. Data for K-type stars havebeen circled to better distinguish them from G-type star data.

interesting applications to planetary systems with a magnetically active central star werediscussed, by extrapolating theoretical models to predict the amplitude of the observedorbital period variations for different stellar rotation periods corresponding to differentlevels of magnetic activity (cf. Fig. 2.16) (see also Sect. 2.2.6).

Lanza and Rodono reviewed at JENAM 2003 (see [67]) the connection between orbitalperiod modulation and magnetic activity in close binaries with an emphasis on the com-parison between observational data for RS CVn systems and recently proposed theoreticalmodels. The orbital period oscillations occurring on timescales of a few decades (see theO−C diagram of the prototype eclipsing binary RS CVn in Fig. 2.17) may be accountedfor by means of a standing torsional Alfven wave in the convection zone of the magneti-cally active components of such systems in the framework of the hypothesis proposed byApplegate (1992). Two resonant excitation mechanisms based on the coupling betweenthe wave and a αΩ dynamo are preliminary discussed.

2.2.1.4 Evolution of stellar magnetic activity and related phenomena

”The Sun in time” project. Messina in collaboration with E. F. Guinan (Villanova Uni-versity, PA/USA) continued to carry out a multi-wavelength study of solar analogues withages from ∼ 100 million years to 9 billion years as part of The Sun in Time project. Thedata for this program are obtained with NASA and ESA satellites such as ASCA, ROSAT,XMM, Chandra, EUVE, FUSE, IUE and HST. Also, observations of most of these starsare being made with Villanova’s 0.8 meter robotic telescope (FCAPT) in Arizona. Themain scientific goals are (a) to study the solar magnetic dynamo (with rotation as theonly variable) and (b) to determine the radiative and magnetic properties of the youngSun.


Figure 2.16: The expected relative orbital period variation of a star-planet system versusthe orbital period of the planet according to the model by Lanza & Rodono (1999).The central star is assumed to be a late-type dwarf of mass M = 0.7M and radiusR = 0.86R. The plots are labelled by the rotation period Prot of the central star,respectively – Prot = 3 days: solid line; Prot = 10 days: dashed line; Prot = 30 days:dotted line.

Messina and Guinan [37], [105] have investigated the presence of surface differentialrotation (SDR) in a subsample of five young single G0-G5V stars with ages between 130Myr and 700 Myr: EK Dra, UMa, HN Peg, k1 Cet and BE Cet. Also they include in thisstudy the Pleiades-age ( 130 Myr) K0V star DX Leo (HD82443).

The periodogram analysis of the photometric data time series has allowed to deter-mine the rotational periods and to derive the following results: i) periodic variations ofthe rotational period are present and in phase with the starspot cycle for BE Cet and DXLeo; likely periodic and in phase for π1 UMa, EK Dra and HN Peg, but still needing con-firmation. By analogy with the solar butterfly diagram, the rotational period variationsare interpretable in terms of surface differential rotation; ii) BE Cet, π1 UMa and EK Drashow a solar-like pattern of SDR, that is the rotational period steadily decreases along theactivity cycle, jumping back to higher values at the beginning of the next cycle (left panelof Fig 2.18); on the contrary, DX Leo, k1 Cet and HN Peg show an antisolar pattern (rightpanel of Fig 2.18); iii) the amplitude of the rotational period variations shows a powerlaw dependence on the rotational period (left panel of Fig 2.19); the cycle length is notcorrelated to the Dynamo number, while stars tend to concentrate along three differentbranches with the cycle length increasing with increasing ∆Ω/Ω (right panel of Fig 2.19).Moreover, the SDR amplitude is found to change from cycle to cycle, which is reminiscentof a wave of excess rotation propagating in latitude; iiii) the apparently different solarand antisolar behaviours are probably due to different inclinations of the stellar rotationaxis under which the star is seen. The long-term photometry of the young single star LQHya, although not included in the initial project, is also used in the present analysis toenlarge the investigated sample. Three different starspot cycles were determined for LQ


Figure 2.17: Upper panel: The (O − C) of the primary eclipses of RS CVn versus time.The reference ephemeris is: Min I = 2410102.4280 + 4.797817 × E, where E is thenumber of orbital cycles elapsed from the initial epoch. The dashed line is a third-orderpolynomial best fit to the data. Middle panel: The residual (O−C)I versus time obtainedby subtracting the third-order polynomial fit to the (O−C) variation in the upper panel.A short-term modulation of the orbital period is clearly apparent with a cycle of about40 yr. Lower panel: The total spotted area on the K2IV active component of RS CVnversus time as derived by the analysis of Rodono et al. (1995). The period of the spotcycle is about 20 yr.

Hya and an antisolar pattern of SDR.

S. Messina started a collaboration with astronomers P. Parihar of Indian Instituteof Astrophysics (IIA) andB. J. Medhi of Gauhati University (Assam) for a long-termphotometric monitoring of open stellar clusters of different ages with the 2-m HimalayanChandra Telescope (HCT) of IIA to study the evolution of rotational period distributionand magnetic activity of active late-type stars.

Investigation of star forming regions. Within a collaboration with Covino and Al-cala from INAF-Napoli Observatory, Frasca, Catalano and Marilli [25] have identifiedand characterized 22 ROSAT All-Sky Survey (RASS) X-ray sources distributed in thegeneral direction of the Orion star-forming region. The optical identifications are basedon intermediate-resolution spectroscopy and UBV Johnson photometry using the 91-cmtelescope of Catania Astrophysical Observatory. The strengths of the Hα, Nai D2 andlithium lines for the stellar counterparts are evaluated applying the spectral subtractiontechnique, using templates of the same spectral type. Radial velocities of the opticalcounterparts are also reported. Thirteen of the optical counterparts show the lithiumabsorption line in their spectra and have radial velocities consistent with the Orion starforming region. Four of these objects can be classified as new bona-fide T Tauri stars onthe basis of the kinematics and of the high lithium content (Fig. 2.20).


6.45

6.40

6.35

6.30

V m

agni

tude

BE Cet Prot

= 7.405-8.030 (d) P cyc 1

= 6.7 (yr)

1985 1990 1995 2000

year

6000 7000 8000 9000 10000 11000 12000HJD -2440000

6.0

6.5

7.0

7.5

8.0

perio

d (d

)

Cycle I Cycle II Cycle III

7.20

7.15

7.10

7.05

7.00

6.95

V m

agni

tude

DX Leo Prot

= 5.345-5.476 (d) Pcyc

= 3.21 (yr)

1988 1990 1992 1994 1996 1998 2000year

7000 8000 9000 10000 11000 12000HJD -2440000

5.20

5.30

5.40

5.50

perio

d (d

)

Cycle I Cycle II Cycle III Cycle IV

Figure 2.18: (top panels) Long-term V-band brightness variations of BE Cet (left)) andDX Leo (right). (bottom panel) Seasonal rotation periods vs. time with a linear fit todata. The rotation period monotonically decreases along the starspot cycle showing asolar-like behaviour for BE Cet (left) and anti-solar for DX Leo (right).

Figure 2.19: (left panel) The rotational period variations (∆P) are plotted vs. the meanrotational period. Bullets, asterisks and pluses denote solar, antisolar and hybrid SDRpatterns, respectively. The continuous line is a power law fit to the whole sample, whilethe dotted line is a power law fit to G-type stars only. (right panel) The cycle frequency(ωcyc) is plotted vs. the relative surface differential rotation amplitude (∆Ω/Ω). Starstend to concentrate along three different branches. Vertical dotted lines connect multiplecycles. The dashed arrows for targets D, S and N indicate the existence of a long-termtrend superimposed on the detected cycle. Symbols and labels have the same meaning asin the left panel.


Figure 2.20: Li i equivalent width of our PMS candidates plotted as a function of (B−V )0

color index (filled circles). Li i EWs for Pleiades stars are represented by plus symbols.The upper envelope of these latter EWs is marked with a full line. Big dots indicatebona-fide WTTS stars, four of which are new detections.

2.2.1.5 Systematic observations and activity cycles

Cutispoto, Messina, and Rodono have presented the UBV(RI)c photometric observationsof 18 active stars observed at ESO and with the APT at the Catania AstrophysicalObservatory in 1994, pointing out for many stars the variations of the photometric periodand of the surface fraction covered by photospheric spots. Some spectral classificationsof the observed stars have been revised and improved.

Messina, Cutispoto and Rodono [106] have discussed the feasibility of systematic pho-tometric observations by means of robotic telescopes, for instance the REM (Rapid EyeMount), to characterize the level of magnetic activity in candidate stars hosting planetarysystems.

2.2.1.6 Dynamo theory of stellar magnetic fields

Bonanno A., Elstner, Rudiger and Belvedere have presented the results of numericalsimulations of the solar dynamo both for given rotation law and meridional flow in thecase of a low eddy diffusivity of the order of 1011 cm2s−1 known from the sunspot decay.They show that if the helioseismologically derived internal solar rotation law is considered,a model without meridional flow of high magnetic Reynolds number (corresponding tolow eddy diffusivity) fails in all the three issues in comparison with the observations.However, a meridional flow with equatorial drift at the bottom of the convection zoneof few meters by second can indeed enforce the equator-ward migration of the toroidalmagnetic field belts similar to the observed butterfly diagram but, the solution has onlya dipolar parity if the (positive) alpha-effect is located at the base of the convection zonerather than at the top [61]. Although is widely accepted that dynamo action is veryeffective in stars with deep convection zone significant generation and amplification ofmagnetic field is possible in thin convective instabilities. As an extreme case Bonanno,A. in collaboration with, Rezzolla and Urpin have investigated the turbulent mean-fielddynamo action in protoneutron stars that are subject to convective and neutron finger


instabilities [8]. While the first one develops mostly in the inner regions of the star, thesecond one is favoured in the outer regions, where the Rossby number is much smallerand a mean-field dynamo action is more efficient. By solving the mean-field inductionequation they have computed the critical spin period below which no dynamo action ispossible and found it to be ≈1 s for a wide range of stellar models. Because this criticalperiod is substantially longer than the characteristic spin period of very young pulsars, itis expect that a mean-field dynamo will be effective for most protoneutron stars.

Recents achievements on the dynamo theory are being reviewed by L. Paterno in apaper to be published on AIP. The highly non-linear problem of magneto-hydrodynamicsof stellar plasmas, and various approaches experienced for its solution, from the linearizeddynamos, to the asymptotic dynamos, useful for stars in that simple relationships betweenthe relevant parameters are derived, to the non linear and eventually fully hydromagneticdynamos in which the whole set of equations are solved at once, by means of very sophis-ticated two- or three-dimensional numerical codes is discussed.

2.2.2 Stellar oscillations and asteroseismology

INAF Researchers: A. Bonanno, M. P. Di Mauro, A. Frasca, A. F. Lanza,R. Ventura

University Researchers: L. Paterno, M. RodonoPhD students: S. LecciaStudents: G. Mignemi

The activity of the stellar oscillation group during the year has been devoted to theseismological analysis of stars which have been selected as primary science targets forground-based observational campaigns or for upcoming space missions, and to the inves-tigation of new asteroseismic techniques and methods to extract information on specificfeatures of the internal structure of the stars from few modes of oscillation.

A. Bonanno, M. P. Di Mauro, R. Ventura in collaboration with L. Paterno, S. Lecciaand G. Mignemi join a collaborative national project on “Asteroseismology”, which in-cludes a group of the INAF-Astronomical Observatory of Monte Porzio Catone - Rome(F. D’antona et al.) and a group of the INAF-Osservatorio Astromonico di Brera - Mer-ate (E. Antonelli et al.). This project, which has been partially supported by MIUR,Ministry of Education, University and Research, for the period December 2002-December2004, aims to join the different expertises and skills of italian researchers which have along experience in the field of asteroseismology.

A part of the activity has been also devoted to the coordination of the Catania’s groupparticipation to the Eddington mission, which was proposed in May 2002 as part of theEuropean Space Agency’s new Science Program “Cosmic Vision” with the primary goalsof extra-solar planet hunting by transits, and the determination of multi-mode oscillationsof stars for asteroseismic investigations of stellar structure and evolution. UnfortunatelyEddington mission was removed from ESA Science programme by the Science ProgrammeCommittee at its 105th meeting held on November 5-6, 2003.


2.2.2.1 Solar-type stars

M. P. Di Mauro in collaboration with L. Paterno, J. Christensen-Dalsgaard of the Uni-versity of Aarhus, DK and F. D’Antona of the INAF-OAR have concluded the theoreticalinvestigation, already started in 2002, on the star η Bootis. η Boo is considered a verygood candidate for asteroseismic studies. It is a well-observed bright star, whose oscil-lations, similarly to those observed in the Sun, are believed to be excited stochasticallyby turbulent convection. Its spectrum is characterized by a large frequency separation∆ν = (40.47± 0.05)µHz and a small frequency separation δν = (3.06± 0.14)µHz.In [24]and [55], Di Mauro et al. showed how accurate observations of oscillation frequenciesused together with the spectroscopic and photometric estimates of the basic parameterscan successfully constrain the structural properties of such a pulsating star and lead tothe determination of the stellar model which best reproduces the observations.

Figure 2.21: On the left panel: Evolutionary tracks plotted on the HR diagram calculatedwith M = 1.71M, the observed metallicity (Z = 0.04), the OPAL equation of stateand increasing values of overshooting parameter αov. The rectangle defines the one-sigmaerror box for the observed luminosity and effective temperature of η Boo, which accordingto these evolution tracks appears to be in the post-main-sequence phase. On the rightpanel: Echelle diagram for a model for a post-main-sequence phase star together withthe observational results. Theoretical and observed frequencies are plotted with ∆ν =40.47µHz. Circles are used for modes with l = 0, triangles for l = 1, squares for l = 2,and diamonds for l = 3. The filled symbols with error bars show observed frequencies anderrors (Kjeldsen et al., 2003), plotted by using ν0 = 726µHz. The open symbols representthe computed frequencies plotted by using a reference frequency ν0 = 704µHz. The sizeof the open symbols indicates the relative surface amplitude of oscillation modes. Crossesindicate modes with small predicted amplitude (e.g. g modes).

M. P. Di Mauro calculated a set of stellar evolutionary sequences by using stellarevolution code by Christensen-Dalsgaard tuned to match the the observed luminosity andeffective temperature of η Boo, by varying the metallicity in the range of the observederrors, considering the inclusion of convective overshooting, and testing the use of differentequations of state and of different formulations for the convective transport. Then, sheused the Aarhus adiabatic oscillation code to calculate the p-mode eigenfrequencies withharmonic degree l = 0, 1, 2, 3 for a selected family of models all consistent with theobserved basic parameters and characterized by the variables which are not determined by


Figure 2.22: On the left:Evolution tracks plotted in an HR diagram for several masses,assuming the observed metallicity Z = 0.04, OPAL equation of state and increasing valuesof the extent of the overshooting parameter from the convective stellar core. The rectangledefines the one-sigma error box for the observed luminosity and effective temperature of ηBoo. The inclusion of overshooting allows to consider that η Boo is in the main-sequencephase of evolution. On the right: Echelle diagram for a model in the main-sequence phasetogether with the observational results. Symbols have the same meaning of Fig. 2.21. Theopen symbols represent the computed frequencies plotted by using a reference frequencyν0 = 714µHz

observations, namely the mass M and the age of the star. The problem of identifying theevolutionary state of this star was approached by studying the pulsational characteristicsof the computed models. The interpretation of the theoretical results was obtained notonly by comparing the computed large and small separations with those obtained for theobserved frequencies, but also by studying the echelle diagrams for the different models.

The results are very striking: while for several years, it has been argued (Christensen-Dalsgaard et al., 1995; Guenther and Demarque, 1996; see also [24]) that the locationin the H-R diagram identifies η Boo as a subgiant star in post-main-sequence phase(see Figure 2.21), with a helium core, having exhausted its central hydrogen, in [55] theauthors showed that observations of this star are also consistent with the conditions of aless evolved star in the main-sequence phase (see Figure 2.22). It is evident, but hardlydecisive, that the post-main-sequence phase is a rapid phase of the evolution, which mightbe less likely to be observed. The conclusion was that observations are consistent with twopossible evolutionary scenarios for η Boo: (i) a subgiant star in post-main-sequence phase,with a mass in the range M = 1.64 − 1.75M, which in the main-sequence phase hadno or moderate core overshooting, and whose oscillation spectrum contains frequenciesof nonradial modes with mixed character due to avoided crossings; (ii) a less evolvedstar in the main-sequence phase, with a mass in the range M = 1.75 − 1.9M, whichincludes overshooting from the convective core and has p modes in the observed frequencyrange which show no mixed character and follow the asymptotic theory. In the end, itappeared clear that the accuracy of the existing frequency observations does not allow aclear distinction between the proposed scenarios; It is hoped that in the future the moreaccurate observations from space will enable us to collect a larger amount of high-qualityfrequencies and hence allow a detailed test of stellar modelling and evolution theories.


Figure 2.23: Radial velocity curve measured for Procyon

M.P. Di Mauro has collaborated with A. Miglio from the University of Liegi (Be),J. Christensen-Dalsgaard from the University of Aarhus (DK), M. Monteiro from theUniversity of Porto (P) and M. Thompson of the Imperial College London (UK), on thedetermination of the relations between the details of the internal stellar structure and thecharacteristics of the oscillation spectrum. In fact, it is clear, that some specific featuresof the stellar structure, such as the base of the convective zone, the location of the secondhelium ionization zone, the extent of the core, produce characteristic signals in the largeand small separations, and hence in the frequencies of oscillations. In particular, in [108]and in a paper which is in preparation, the authors have demonstrated that the details ofthe second helium ionization zone can be determined by seismological means. This study,which use theoretical frequencies of stellar models, has the very important objective ofproviding a method to infer the helium abundance in stars from seismology.

A. Bonanno, in collaborations with people of the Padova observatory, partecipated ina program aimed to study oscillations in Procyon. The F5 IV - V sub-giant Procyon wasobserved over six nights with SARG at the beginning of 2001 during its very first approvedguest program. The authors took sequences of ten seconds exposures with an average deadtime in between of 127 s. In total, 956 spectra (R=144,000) were collected with a typicalsignal to noise ratio ranging between 250 - 330. Data reduction was performed usingIRAF tasks devoted to echelle spectra. Successively the modeling of the star plus iodineabsorption spectra was performed by using AUSTRAL code (Endl et al. 2000, A&A, 362,585) in order to obtain the radial velocity time series. The single points of the Dopplershift measurements have an r.m.s. internal error of 1.68 m/s. As shown in Fig. 2.23, insome time series we obtain an internal error of 1.5 m/s and the 21 minute pulsation isclearly visible where there is not negative interference with other pulsation mode.

Scargle and Lomb modified periodgram shows a power excess around 1mHz. Theoverall shape of the excess power is not symmetric and does not have the typical bell-likeenvelope of the solar oscillations. This can be explained by the effects of gaps and/ ornoise and amplitude modulation that are intrinsic to the star.

The higher power frequency corresponds within the observational error (2 Hz) to the0.7787 mHz identified by Martic et al. (2004 astro-ph 043035) as np=-1 and l=1 mode.The analysis of the modes is in progress, but we could already detect new structure athigher frequencies in the power spectrum.


Figure 2.24: Power spectrum of oscillations measured in Procyon

Preliminary results have been presented in JENAM 2003. An additional contributionin GONG’04 has been also scheduled. A paper is in preparation.

2.2.2.2 Asteroseismology of hot subdwarf stars

During a photometric campaign dedicated to the hot subdwarf B (sdB) stars, A. Bonanno,Frasca, S. Catalano, Paterno and Mignemi discovered short period oscillations in PG1613+426 from time-series photometry carried out with the 91-cm Cassegrain telescope.This star, which is brighter than the average of the presently known sdB pulsators, withB = 14.14 mag, has Teff = 34 400 K and log g = 5.97, is located near the hot end of thesdB instability strip. It displays a well-observed peak in the power spectrum at a periodof 144.18 ± 0.06 s. This star seems to be well-suited for high-precision measurements,which could detect a possible multi-mode pulsation behaviour [5].

A. Bonanno in collaboration with R.Silvotti (INAF - Osservatorio Astronomico diCapodimonte), has organized a multisite photometric campaign on the multiperiodic sdBstar PG1325+101 star. The folowing observatories have been partecipating: Baker andKitt Peak (USA), BOAO (Korea), BAO (China), WISE (Israel), Moletai (Lituania), Serrala Nave and Loiano (Italy), La palma (Spain). Preliminary results have presented at themeeting in Keele (UK), June 2003, EHB stars and related objects.

2.2.2.3 Conferences and Meetings Committes

• M. P. Di Mauro was member of the Scientific Organizing Committee of the 2nd Ed-dington Workshop ”Stellar-structure and habitable planet finding” held in Palermoin April 9-11, 2003. The workshop was intended as an invitation to the internationalscientific community involved in the Eddington mission - both the planet findingand asteroseismology phases. The main topics covered at the workshop were: themission baseline’s and possible options, selection of the planet field, possible scien-tific targets for the asteroseismology part, possible/required data products for eachscientific goal, ”support” science needed to be done by the community ahead of themission.

• M. P. Di Mauro was member of the Scientific Organizing Committee of the JD 12“Solar and Solar-like oscillations: insights & challenges for the Sun and Stars”,


IAU XXV General Assembly , July 18-19, 2003, Sydney (Australia). This jointdiscussion covered the subject of ‘solar-like’ oscillations, i.e. those that are excitedstochastically by convection and occur in the Sun and in solar-type stars. Thesession concerning Asteroseismology was dealing with following the topics: theo-retical investigations: stellar models and oscillation amplitudes, observational tech-niques: velocity and photometry measurements, relationship to exoplanet searches;frequency extraction, observational results: ground-based velocity measurements;space-based photometric measurements

• M. P. Di Mauro was one of the organizers of the Workshop “Searching for Planetsin the Habitable Zone”, Italian Participation to the Eddington Mission, held at theINAF- Astronomical Observatory of Monte Porzio Catone (Rome) in October 17-18,2003. The workshop was organized with the aim of combining the common effortsof all the italian scientist interested in the realization of the Eddingtom Mission,i.e. the exo-planets community and the researchers interested on the application ofasterosemolgy for the study of stellar structure.

2.2.3 Chemical composition studies and chemically peculiar stars

INAF Researchers: G. Catanzaro, F. LeoneIRA Researchers: P. Leto, C. Trigilio, G. Umana

Chemical Peculiar (CP) stars of the Main Sequence show several characteristics that couldbe summarized in i) a non-standard chemical composition of their atmospheres and ii) ina variability that involves their luminosity, spectrum and magnetic field.

2.2.3.1 Magnetic Field

Measurement of magnetic fields: By means of circular spectropolarimetry, it is possible tomeasure the effective magnetic field of CP stars, i.e. the line-intensity weighted averageover the visible stellar disk of the line-of-sight component Hz of the magnetic field vector.

Usually, Heff values obtained from lines of different elements are statistically combinedwith the aim to improve the precision of the effective field measurement. However, becauseof the non-homogeneous distribution of the elements, such an operation is not a prioriexpected to lead to any improvement and moreover its validity has yet to be proved.

In this framework, Leone and Catanzaro have decided to quantify the importance ofthe non-homogeneous distribution of elements in measuring Heff , and have to this purposecarried out high resolution spectropolarimetric observations of the CP star HD 24712 atthree rotational phases. The spectra have been obtained at the Telescopio NazionaleGalileo equipped with the SARG spectrograph and the polarimetric module. This researchis still in progress.

Magnetic fields from near-IR lines: Zeeman splitting of a line, on the other hand, providesthe most direct method for the detection and measurement of stellar magnetic fieldsand displays little sensitivity to the mean field orientation. The average wavelengthdisplacement of the σ components from the central line position λ0 (in A) is given by

∆λ = 4.67× 10−13 geff λ20 B


AngstromsAngstroms

AngstromsAngstroms

AngstromsAngstroms

Figure 2.25: The Fei λλ 15648.258, 15652.874 and 15662.016 A line profiles (histograms)of HD 180583 can be matched with a null magnetic field assuming rotational velocityof 7.5 km s−1. Dashed lines represent line profiles computed for a 0.5 kG field, nullmicroturbulence and norotational broadening.

where geff is the effective Lande factor and B is the magnetic field strength expressed inGauss.

Because the displacement of the Zeeman components is proportional to the square ofthe wavelength, while the non-magnetic line broadening increases only linearly in wave-length, disentangling magnetic effects from other broadening mechanisms becomes mucheasier with high resolution spectroscopic observations in the near-infrared, rather thanthe optical, wavelength region. Leone, Vacca (Dept. of Astronomy, Univ. of California,Berkeley) and Stift (Institut fur Astronomie, Universitat Wien) [33] have carried out high-resolution spectroscopy with CSHELL on the NASA Infrared Telescope Facility on MaunaKea of the 15625-15665 A region for two MCP stars, viz. HD 176232 and HD 201601, andfor the suspected MCP star HD 180583. An example of such study is reported in Fig. 2.25.

Magnetic fields in the β Lyrae system: The spectroscopic and eclipsing binary systemβ Lyrae shows a very complex behavior both from a photometric and a spectroscopicpoint of view. Visible light curves are characterized by a ∼1 mag deep primary minimumand a ∼0.4 mag secondary minimum. Usually this is explained assuming that the starwhich is in front at the primary minimum is larger and of lower surface brightness thanthe star that is behind. In the case of β Lyrae system, the cool star would have to be aF5 star, whose characteristic lines are not present in the spectrum and that is not visiblein the near infrared. So the photometric behavior of β Lyrae was understood only afterthe suggestion that the more massive component is surrounded by a flat and opaque disk.

The presence of a magnetic field in β Lyrae was firstly suggested by Babcock in 1958and then confirmed by Skulsky in 1982. This kG-order large-scale organized magneticfield has been neglected in interpreting and modeling the large variety of phenomenapresented by β Lyrae.


Figure 2.26: Effective magnetic field in kG of β Lyrae measured in 1980-1988, 1993-1995,1999 and 2000. Data are folded with the orbital period of 12.91378 days. Dashed linesrepresent the null value. Among the 1993-1995 data, triangles represents 1993, circles the1994 and crosses the 1995 observations respectively.

Leone, Plachinda (Crimean Astrophysical Observatory, Nauchny, Crimea), Umana(IRA, Noto), Trigilio (IRA, Noto) and Skulsky (Lviv Polytechnic University, Lviv, Ukraine)[32] rised several reasons to study the magnetic field of β Lyrae. If the observed magneticfield is really located on the brightest star, it would be the only known B-type giant starwith a measurable magnetic field. Interest in understanding the magnetic field of β Lyraesystem comes from the high energy phenomena: X-ray and radio emission. Moreover,mass transfer and accretion disk could be very different than believed up till now, as theyhave been modeled neglecting the presence of such a strong magnetic field.

Leone and collaborators found that the magnetic field as measured from metal linesof the brightest component is of kG order, and it changes with the orbital period, and ona longer time scale. Unfortunately, their data are not sufficient to conclude if this fieldchanges periodically or abruptly.

Assuming that the magnetic field belongs to the brightest star, the straightforwardconclusion is that this is the first B-type giant whose magnetic field has been measuredwith certainty. In this case, the magnetic field variability with the orbital period isindicative of rotation-orbit synchronism and the long-time variability could be related tothe dynamo period. However, we cannot rule out that we measure the field generated inthe accretion disk on the brightest component.

2.2.3.2 Chemical Abundances

In the attempt to study the chemical composition of stars, a very important task isthe modeling of their atmosphere. A good model is a fundamental starting point for adetailed quantitative analysis of the chemical composition. This importance is stressedin the case of CP stars, for which the overabundances of metals change the structure of


Figure 2.27: Comparison between theoretical and observed spectra in the FUV range λ1000 - 1098 A. In each box we have: at the top the ISM model (green line) with labelledthe identified lines, at the middle the synthetic photospheric model (blue line) with theidentified lines and at the bottom, the observed spectrum compared with the total model(red line).

their atmospheres.

The most reliable codes used at the moment for such purposes are the Kurucz’s ATLASand SYNTHE. These programs have been extensively and successfully used to modeloptical spectra of stars whose spectral types lie between B and A.

With the advent of new instruments from space, new spectral windows are openedfor researchers. Recently, Far-UV (namely wavelength shortward Lyα) high resolutionspectra become available thanks to the Far Ultraviolet Satellite Explorer (FUSE).

HD 207538: A new question arises: are the available codes able to reproduce the spec-tra observed at those wavelengths? To try giving an answer to this question, Catanzaro,Andre (Institute d’Astrophisique de Paris, France), Leone and Sonnentrucker (Johns Hop-kins University, Baltimore, MD, USA) modeled the observed spectrum of HD 207538 (BOV) from far-UV to visible with a single set of stellar parameters. Optical spectrum of thisstar has been obtained with the high resolution spectrograph (SARG) at the TelescopioNazionale Galileo. UV and far-UV spectra have been extracted from the IUE and FUSEarchive respectively. ATLAS9 has been used to compute the model of the atmosphereand SYNTHE to reproduce the observed spectrum.

Because of the inter-stellar matter (ISM) presents between the star and us, the FUSEspectrum is strongly contamined by ISM spectral lines. Thus, an abundance analysis ofthe ISM material toward the line of sight of HD 207538 was needed. The ISM theoreticalspectrum has been computed with the code OWENS developed by M. Lemoine and theFUSE French team. This spectrum has been combined with the one computed withSYNTHE and the result has been compared with the observations.

As a result of this study [12] they were able to reproduce the observed spectrum ofHD 207538, including also the ISM features, with a single set of atmospheric parameters


Figure 2.28: Comparison between the observed and computed Hδ and Hγ lines. Eachprofile has been calculated using models with different ODF tables.

(Teff = 32190 K, log g= 4.32 and ξ= 8 km s−1) and chemical abundances.

On the determination of Teff and log g: Non evolved early-type stars play a key role inmany aspects of modern astrophysics. Since their radiative atmospheres are particularlystable, their surface abundances reflect those of the formation regions from which theyoriginated. Hence, a correct determination of these abundances is the primary task to fulfilin any study, from the chemical gradient in the Milky-Way to the evolution of externalgalaxies.

One of the most accurate methods commonly used to infer Teff and log g is based onthe comparison of the observed and theoretical profiles of Balmer lines. Several studieshave shown that a non-standard chemical composition of the stellar atmosphere alters theflux distribution of the star or modifies the profiles of the Balmer lines.

Catanzaro, Leone and Dall (ESO) investigated how an extremely non standard at-mosphere can influence the determination of the fundamental parameters. With thisaim they extracted HR 6000 from a sample of high resolution spectroscopic observationscollected by means of FEROS@ESO.

Fig. 2.28 shows the importance of helium and metal abundances when we try todetermine Teff and log g matching balmer line profiles. Neglecting the correct He andmetal abundances, two models, 400 K and 0.07 dex different in Teff and gravity, arenecessary. The results of this study have been submitted to Astronomy & Astrophysicsfor pubblication.

2.2.3.3 Spectrum variability

Pulsations in roAp star γEqu: The rapidly oscillating Ap (roAp) stars provide a uniqueopportunity to study the interaction of stellar pulsation, rotation and strong global mag-netic fields.


Figure 2.29: The amplitude spectra for the effective magnetic field strength for the NdIII λ5845.07 A line data. The highest peak has a period of 12.1 min and agrees well withthe known photometric pulsation periods.

These observational and theoretical advances naturally lead to the question of whatmagnetic variations occur over the pulsation cycle in roAp stars. It is clear from theoblique pulsation that the magnetic fields strongly control the pulsation geometry, andthey are thought to have strong impact on the unknown excitation mechanism.

Leone and Kurtz (Centre for Astrophysics, University of Central Lancashire, UK)[31], with the aim to obtain higher precision measurements of the magnetic field over thepulsation period, decided to use high resolution spectropolarimetry on individual lines inthe bright roAp star γ Equ. This star is known to have multiple pulsation periods near 12min and high radial velocity in some spectral lines. They made the first clear detectionof magnetic variations over the pulsation cycle in a roAp star. γ Equ shows magneticvariations up to 240 ± 37 G with a period of 12.1 min, a period in good agreement withthe known photometric pulsation periods (see Fig. 2.29).

Helium variability: To try to understand the behavior of helium variability in CPstars, Catanzaro and Leone [14] continued the on-going observational campaign startedtwo years ago (Catanzaro et al., 1999). They performed new time-resolved spectroscopicobservations of the HeI5876 A line for a sample of 10 stars in the spectral range B3 - A2and characterized by different overabundances. The observations have been performedwith the spectrograph of the 91cm telescope of the stellar station ”M. G. Fracastoro” ofthe Catania Astrophysical Observatory.

In the scenario described by the Oblique Rotator Model spectroscopic, photometricand magnetic data should vary with the same period. Since the work of Mihalas (1973),the variability of the line strength of helium lines has been explained with the presence oflarge caps of such element placed around the magnetic poles. In such a way the rotationof the star is responsible of the observed spectral variability.

Principal aim of this kind of studies is to explore the phase relations among spectral,light and magnetic variations searching for correlations with physical properties of thestars, for example: spectral types or chemical peculiarities.

Thanks to this new data-set, the authors explored the possible relations with pecu-liarity classes and lengths of the rotational periods. But, they confirmed the previouslypublished conclusions (Catanzaro et al., 1999), that is: no-unique correlation exists and


Figure 2.30: Equivalent width variations of HD 124224 (left) and HD 142990 (right). ForHD 124224, equivalent widths of the HeIλ4471 A has been taken from Kuschnig et al.(1999). Magnetic data are displayed with different symbols: open circles for Borra (1980)data while filled circles for Pyper et al. (1998). For HD 142990, magnetic observationscome from Borra et al. (1983). Photometry for both objects is taken from Hipparcos

this fact is independent of the Teff of observed stars, the peculiarity classes and the periodsof variations. As an example, we reported in Figs. 2.30 the observed spectral variabilityfor HD 124224 and HD 142990.

HgMn in binary systems: During 2003, Catanzaro, Leone and Leto continued a cam-paign devoted to the study of the spectroscopic binary stars with a chemical peculiar(HgMn) component. They selected 34 systems in total and for the 27 already observedthey are calculating orbital parameters, by means of an IDL procedure that compute thebest orbital solution minimizing the differences between observed and theoretical veloci-ties, written by the authors.

From this sample they extracted the SB2 system HD 191110 [15]. For such a star wereused also spectra from the CFHT archive. The aim of this study was to perform thefirst quantitative abundance analysis of the components. From the simultaneous fit ofthe composite Hβ profiles (Fig. 2.31, left panel) the authors determined the Teff and log gof each component and the light ratio between them. The isotopic structure of the Hgiλ3984 A has been studied as well (Fig. 2.31, right panel).

Moreover, Catanzaro and Leto [54] defined orbital parameters for six SB2 systems ofthis sample. In particular, HD 173524 and HD 216494 are triple systems: for the firstobject they improved the solution of the orbit and estimated the eccentricity of the thirdcompanion (Fig. 2.32, left panel), for the second system they firstly identified the signatureof the Hβ of the third component (Fig. 2.32, right panel). A preliminar analysis of thisstar has been presented [134].


Figure 2.31: Left panel - Simultaneous fit of the composite Hβ of HD 191110. The ob-servations have been carried out at the 91 cm telescope of the Catania AstrophysicalObservatory with R = 14000. Right panel - Simultaneous fit of the composite spectrum inthe region of the Hgi λ3984 A.

Figure 2.32: Left panel shows the radial velocity curves for HD 173524 A and B (bottom)and for the motion of the center of mass due to the third companion (top). Right panelshows the composite Hβ observed in HD 216494.


2.2.4 Search for brown dwarfs

INAF Researchers: A. Magazzu

Magazzu, togheter with collegues at IfA, CFHT and Grenoble Observatory, has searchedfor brown dwarfs in a CFHT survey of the Taurus star-forming region [103]. In particular,infrared spectra of brown dwarf candidates, obtained with NICS at Telescopio NazionaleGalileo, led to the discovery of six new substellar objects [104]. Together with collegues ofArcetri and Telescopio Nazionale Galileo, a new classification scheme for infrared spectraof very cool objects has been presented [122].

2.2.5 Nuclear astrophysics

INAF Researchers: A. BonannoUniversity Researchers: R. A. ZappalaPhD Students: L. Iapichino, G. Palazzo, R. G. PizzoneFellow: V. Costa

Introduction: Since approximately a decade, a group of researchers of Osserva-torio Astrofisico di Catania (OAC), Dipartimento di Fisica ed Astronomia and Diparti-mento di Metodologie Fisiche e Chimiche per l’Ingegneria of University of Catania, IstitutoNazionale di Fisica Nucleare (INFN) and Laboratori Nazionali del Sud (LNS) have beenmaintaining a scientific collaboration on topics concerned with the nuclear astrophysicsresearch field, and devoted both to experimental and theoretical activities.

The s, r and p processes: It is known that the exo-thermic fusion reaction processesresponsible for energy production in stars are not able to account for the production ofisotopic species heavier than 56Fe. The trans-iron elements are produced instead in threedifferent processes named with the following letters: s, r and p.

A complete and self-consistent model for the origin of the p isotopes is still under study.However one of the most promising models puts the p nucleosynthesis on the Ne-O layerof massive stars (MZAMS & 10M) during their pre-supernova phase or their explosion astype II supernova, through “photo-erosion” of neutrons, α particles and protons involvingheavy (A & 75) isotopes previously formed via the s process (specifically via the coreHe-burning s process named “weak component” of the s process). So the uncertaintiesof the “weak” s process have a direct impact on the p process model because the ssynthesized nuclei are the “seed” for the development of the p process (the “weak” sprocess is responsible for the production of s nuclei in the 60 . A . 90 mass range,where the upper limit and the overall efficiency of the process are still quite uncertaindue to both nuclear reaction rates uncertainties and uncertainties due to stellar evolutionmodelling).

In this framework, after the investigation of some uncertainties due to reaction ratesof key reactions like 22Ne (α , n) 25Mg and 22Ne (α , γ) 26Mg [89], V. Costa, M.L. Pumoand R.A. Zappala (in collaboration with A. Bonanno as regards the calculation of stellarevolution models) examined the impact of poorly modelled convection on the s processyields of the core He-burning phase of massive stars [135]. Attention has been concentratedon the role of overshooting and of the impact of variations of the overshooting parameteron the s process outcome. This task is performed through s process simulations based


on stellar evolution models of a 25 M star (ZAMS mass) with initial solar metallicity,evaluated with the Garching Stellar evolution code Star2003, and through a specificallywritten s process nucleosynthesis code which makes use of a equation solving numericalapproach based on the implicit Kaps-Rentrop method (this method provides an estimateof the “truncation error” associated with each single step integration, so that settingsconcerning to precision requests can be based on truncation error constraints).

2.2.6 Search for extra-solar planets

INAF Researchers: G. Bonanno, R. Cosentino, A. F. Lanza, I. Pagano, S. ScuderiUniversity Researchers: M. Rodono

Since 1995, when the Jupiter-like planet 51 Peg b (Mayor & Queloz 1995) was dis-covered, identification and study of extrasolar planets are between the main goals ofthe international astronomical community. The final aim will be the discovery of otherhabitable planets and/or the confirmation of existence of life on them.

2.2.6.1 Radial velocity exo-planet search

Since year 2000 the SARG team (i.e., the researchers and technicians who participated tothe design and building of the high-resolution spectrograph for the Telescopio NazionaleGalileo, among whom the Catania technological group, led by G. Bonanno, Cosentinoand Scuderi, have been playing a fundamental role) has undertaken a program to searchfor planets in binary systems. The Catania group is responsible for the observationsperformed at Galileo and for part of the data reduction and analysis. The results of thesurvey are high precision radial velocity measurements (typical accuracy ∼ 5 m/s) andhigh precision abundance analysis of the two components of each system. The status ofthe SARG extrasolar planet search has been reviewed by Gratton et al 2003 (Mem.SAIt,75, 97).With the observations gathered up to 2002 we had found one candidate exo-planetsaround component B of the system HD 219542. During 2003 we have performed severalother measurements trying to confirm this detection. Data analysis is in progress and theresults are foreseen for the first months of 2004.

2.2.6.2 Modelling stellar magnetic activity for planetary transit search

Lanza, Rodono and Pagano, in collaboration with P. Barge and his group at the Labo-ratoire d’Astrophysique de Marseille, investigated the effects of stellar magnetic activityon planetary transit detection and developed an approach to reduce the impact of therotational modulation and evolution of the active regions on transit detection. It is basedon the model of solar irradiance variations proposed by Lanza et al. (2003, [29]). Apreliminary assessment of its potentialities for planetary transit detection is presentedin Fig. 2.33 that illustrates how the variability due to active regions can be effectivelymodelled and subtracted making a transit signal easily detected, even during phases ofmaximum solar activity.

Moreover, their model is going to be applied to simulate the variability of solar-likestars, in order to test the algorithms for planetary transit detection to be used by the


Figure 2.33: Upper panel: the TSI variation with superposed the central transit of anEarth-like planet of radius R = 2.2R⊕ and orbital period of 30.0 d around a 1 Mstar. Lower panel: the same time series after subtracting the best fit model light curvecomputed with the model proposed by Lanza et al. (2003, [29]).

Exoplanet Working Group of the space mission COROT (see, e.g., http://www.astrsp-mrs.fr/private/exoplanet/POM/ Corot/Web-Org.html).Results concerning this investigation have been shown in [29; 112; 98].

2.3 Extra-galactic Astrophysics and Cosmology

INAF Researchers: V. Antonuccio, U. Becciani, A. Bonanno, S. CatalanoG. Catanzaro, A. Frasca, E. Marilli, A. Magazzu, S. Scuderi

PhD Students: A. RomeoFellow: D. Ferro

2.3.1 Extra-galactic Astrophysics

2.3.1.1 Observations of BL Lac objects

In collaboration with colleagues of “La Sapienza” Rome University and INAF-TorinoObservatory, A. Frasca, E. Marilli and S. Catalano have carried on photometric U B Vobservations of BL Lac objects, within international programs of short- and long-termmulti-band monitoring (WEBT).

In particular, results of a multi-site optical campaign in which were collected morethan 15 000 observation of BL Lac, from May 2000 to January 2001 have been presented.Cumulative analysis of simultaneous or quasi-simultaneous observations taken at radio(University of Michigan Radio Astronomy Observatory and Metshovi Radio Telescope)and optical (Whole Earth Blazar Telescope [WEBT] collaboration) frequencies, in X-rays

2.3. EXTRA-GALACTIC ASTROPHYSICS AND COSMOLOGY 45

(BeppoSAX and RXTE), and at very high energy gamma rays (HEGRA) has been per-formed ([9]). The WEBT optical campaign achieved an unprecedented time coverage,virtually continuous over several 10-20 hr segments The Catania group has given a sig-nificant contribution to the determination of the “intra-day” variation behaviour and ofthe spectral indices of energy distribution of the source.

The source revealed intraday variability on timescales of 1.5 hr and evidence forspectral hardening associated with increasing optical flux. During the campaign, BL Lacunderwent a major transition from a rather quiescent state prior to 2000 September, toa flaring state for the rest of the year. This was also evident in the X-ray activity of thesource. BeppoSAX observations on July 26-27 revealed a rather low X-ray flux and ahard spectrum. During the July 26-27 observation, there is a tantalizing, although notstatistically significant, indication of a time delay of 4-5 hr between the BeppoSAX andthe R-band light curves. Also, a low-significance detection of a time delay of 15 daysbetween the 14.5 and 22 GHz radio light curves is reported.

Simultaneous optical and X-ray BeppoSax observations of the two BL Lac objectsOJ 287 and MS 1458+22 have been performed in 2001 ([35]). These observations haveallowed the authors to study the spectral energy distribution (SED), which is differentfor the two blazars, but can be well reproduced by log-parabolic spectral laws. Thislaw, already observed for the synchrotron emission components in other blazars, can beexplained if the emitting particles are accelerated by some statistical mechanism havinga probability of energy gain that is a decreasing function of the energy itself.

2.3.1.2 Gamma Ray bursts observation

A. Magazzu has taken part in international observational campaigns aimed at the detec-tion and study of Gamma Rays bursts afterglows, using the Telescopio Nazionale Galileo[18]

2.3.1.3 Hot stars in Local Group galaxies

Local Group galaxies are commonly considered as important astrophysical laboratoriesuseful to study the stars formation history in environmental conditions different fromMilky Way.In this framework Catanzaro, Bianchi (Johns Hopkins University, Baltimore, MD, USA),Scuderi and Manchado (Instituto de Astrofisica de Canarias, Tenerife, Spain) continuedthe effort aimed to characterized the content of two nearby galaxies of the Local Group:M 33 and NGC 6822. We analyzed new spectroscopic data for eight objects (seven starsand the nucleus) in M 33 and three stars in NGC 6822. The observations have been per-formed with the ISIS spectrograph mounted on the 4.2m William Herschel Telescope atthe Observatorio del Roque de los Muchachos (La Palma, Spain).For all the stars they derived important atmospheric parameters such as effective tem-peratures and gravities. For those stars showing clear evidence of emission in Hα, theycomputed also the mass-loss rate [13]. Examples are reported in Fig. 2.34: In summary, inM 33 they found 5 hot star candidates out of 7 stars analyzed, and 2 out of 3 in NGC 6822.Although the limited data quality does not allow a precise measurement of stellar param-eters, our results indicate that the observed fields sample very rich OB associations. Ourspectra add new data-points to the census of hot massive stars in these nearby LocalGroup galaxies.


Figure 2.34: Normalized spectra of stars observed in M 33. The smooth thick lines arethe models for the adopted temperatures and gravities with an estimated wind emission(red lines), and the dashed (blue) lines refer to the photospheric models calculated beforethe mass-loss correction.

2.3.2 Cosmology and Large Scale Structure of the Universe

2.3.2.1 Formation and Evolution of Substructures and Minihalos.

We have performed a high mass and spatial resolution N-body simulation over a boxhaving size ≈ 20h−1 Mpc, on the IBM SP4-512 computing system at CINECA, undera Key Project grant, in collaboration with prof. Andrea Ferrara (SISSA/ISAS, Trieste)and Drs. Giovanni Busarello and Paola Merluzzi (INAF-Osservatorio Astronomico diCapodimonte, Napoli). The main purpose was that of studying the evolution of thestatistical properties of two class of objects: minihalos at high redshifts (6 < z < 10) andin the mass range: 104 ≤ M ≤ 107M, and galaxy-sized halos in Voids. Both these classesof objects are either rare or quite difficult to detect, so that N-body simulations representa unique tool to characterize the statistical properties of these objects. The simulationhas been designed to be subsequently interfaced with eulerian, block-structured AMRgrid codes, in order to allow the study of the evolution of baryons and magnetic fields.An example of the output can be seen in Fig. 2.35. A Void forms within the simulationbox, and a few Clusters are clearly visible around this region. Large underdense regions(Voids) fill a significant fraction of the observed Universe at optical wavelengths, butfew studies exist of galxy population within these Voids, with the notable exception of arecent survey performed by Grogin and Geller (2000, 2001). This simulation will allowus to make the deepest realisation of a density field within an underdense region everattempted until now. Manning (2002) estimates that, along the line of sight towards az ≈ 1.5 QSO, more than 85 % of the Ly-α Forrest is located within underdense region:this fact alone justifies the need to have a numerical sample of minihalos representativeof the true distribution within our Universe.


0 5 10 15 200

5

10

15

20

Figure 2.35: Output of the Cineca Key Project simulation at z=2. Each point representsa Dark Matter halo identified by the HOP group finder (Eisenstein and Hut, 1998), andthey include at least 10 particles, so each halo has a minimum mass of 2.3× 108M.

2.3.2.2 Mechanical heating of the Intergalactic Medium.

Modern cosmological models envisage the existence of two main components of the LargeScale Structure of the Universe: Dark Matter (DM) and the diffuse Intergalactic Medium(IGM). In particular, a significant fraction of Dark Matter is thought to be found ingravitationally collapsed objects (halos), while the IGM can be gravitationally bound toClusters of Galaxies. The motion of DM through the IGM can induce an accretion shock,and some of the mechanical energy can be converted into internal energy of the IGM.The dynamics of this phenomenon on galactic scales was studied in a pioneering paperby Ruderman and Spiegel (1971), and further studied by Hunt (1971), Hunt & Sciama(1972), Schipper (1974) and Lea & De Young (1976). All these studies confirmed animportant fact: mechanical heating from galactic motion can not explain alone the energybudget of the IGM, particularly in Clusters. However, in some circumstances they couldrepresent a significant additional source of energy, which could have an influence on thelocal state of the IGM. We have considerably extended the scope of previous papers onthe subject, which were mostly focussed on the dynamics of the accretion onto the halo.Our main target has been the effect of the shock on the IGM, and for this reason wehave a performed a grid of simulations varying the IGM density and temperature, besidesaccretor’s mass, radius and translational velocity. We have also included a realistic coolingfunction and thermal conduction and viscosity. An example of one such simulation canbe seen in Fig. 2.36. As one can see, even a relatively small halo can affect a significantlylarge region around itself.

2.3.3 Cosmology and Particle Physics

One of the most important problems of modern Physics is the problem of the DarkEnergy, the fact that most of the energy density content of the Universe is contained inthe cosmological term Λ, so that the vacuum energy density ρΛ ≡ Λ/8πG is of the sameorder of the critical density (including dark matter). This problem is deeply connected


Figure 2.36: Accretion shock in the Intergalactic Medium around a Dark Matter halomoving at speed vhalo = 2csound. The simulation is performed in the frame at rest withthe halo’s center of mass. The halo center is located at (1.25, 1), it has a mass M =4× 1011M and a radius R = 150kpc. The IGM has a electron density and temperaturene = 2× 10−2cm−3 and Te = 2× 107K, respectively.

with the problem of the cosmological constant (why is Λ so small?), and therefore itinvolves an overlapping domain between Particle Physics and Cosmology.

The Catania section of INFN, has then supported an ongoing project aimed to addressthis issue, which involves Mainz University (Prof. M. Reuter), the Physics Department ofNaples University (Prof. C. Rubano) and the Naples section of INFN (Dr. G. Esposito).Out of this collaboration, a new approach, based on the renormalization group approachto this problem has been proposed [6]. The following sections are then a brief summaryof what has been achieved in the past year.

In recent years renormalization group techniques have been extensively applied in cos-mology, for instance in classical averaging scenario or in discussing the late-time behaviorof the classical Einstein equations. As for possible quantum gravitational effects, an exactfunctional RG equation for Quantum Einstein Gravity has been introduced and, withincertain approximations (truncations of “theory space”), its predictions for the scale de-pendence of Newton’s constant G and the cosmological constant Λ have been worked out(Reuter, 1998; Lauscher & Reuter, 2001; Lauscher & Reuter, 2002; Reuter & Saueressig,2002).

In particular, it was found (Lauscher & Reuter, 2001) that the ultraviolet behaviorof quantum Einstein gravity is likely to be governed by a non-Gaussian RG fixed pointwhich would render the theory nonperturbatively renormalizable. If so, QEG is math-ematically consistent and predictive at arbitrarily short distances and, in cosmology, attimes arbitrarily close to the initial singularity. In Bonanno & Reuter (2002), the authorsinvestigated how the standard Friedmann-Robertson-Walker (FRW) cosmology gets mod-ified when the scale dependence of G and Λ is taken into account. It is possible to “RG


improve” Einstein’s equation by replacing G→ G(k), Λ→ Λ(k), where k is the runningmass scale which may be identified with the inverse of the cosmological time in a homo-geneous and isotropic Universe, k ∝ 1/t. In this manner the RG running gives rise to adynamically evolving, time dependent G and Λ. The improvement of Einstein’s equationcan be based upon any RG trajectory k 7→ (G(k),Λ(k)) obtained as an (approximate)solution to the exact RG equation of QEG. In particular, if the non-Gaussian UV fixedpoint predicted by all known solutions does indeed exist, G(k) and Λ(k) scale in a verysimple manner as k → ∞. In fact, the dimensionless Newton constant g(k) ≡ k2G(k)and cosmological constant λ(k) ≡ Λ(k)/k2 are attracted towards their fixed point valuesg∗ and λ∗, respectively, In Bonanno & Reuter (2002) the improved cosmology resultingfrom the above relation was analyzed in detail. As the fixed point (g∗, λ∗) is approachedfor k → ∞, it applies to the very early Universe (t → 0). It turned out that the cos-mology of this “Planck era” is described by an essentially unique attractor solution tothe cosmological evolution equations which might provide a solution to the horizon andflatness problems of standard cosmology without invoking an inflationary era1. One of theremarkable properties of the attractor solution is that it dynamically adjusts the vacuumenergy density ρΛ ≡ Λ/8πG so as to equal precisely the matter energy density. In units ofthe critical density, the spatially flat solution has ΩΛ(t) = ΩM(t) = 1

2at any time during

the fixed point era. This adjustment mechanism has led to the speculation (Bonanno &Reuter, 2002) that not only the very early, but also the very late history of the Universeis described by a RG-improved Einstein equation based upon the trajectory (1). In thisscenario one postulates that, in addition to the UV-attractive fixed point discussed so far,there exists a second fixed point (gIR

∗ , λIR∗ ) in (g, λ)-space towards which every trajectory

k 7→ (g(k), λ(k)) within a certain basin of attraction is attracted for k → 0. On very largescales the cutoff identification k ∝ 1/t should still be correct so that for t → ∞ the IRfixed point determines the asymptotically late cosmology. The IR fixed point hypothesisimplies that for k → 0 or t→∞, too, G and Λ evolve accordingly to (1). (In the sequelwe shall omit the superscripts “IR” from g∗ and λ∗ but it should be kept in mind that thevalues of g∗ and λ∗ are different at the two fixed points.) The main motivation for this hy-pothesis comes from the fact that, provided the Universe is spatially flat and has enteredthe fixed point regime already, the densities ΩΛ and ΩM are unambiguously predicted toassume the value 0.5. This is intriguingly close to the values ΩΛ ≈ 0.7, ΩM ≈ 0.3 favoredby recent observations when interpreted within standard FRW cosmology. Hence the IRfixed point might provide a natural solution to the “cosmic coincidence problem” whichdoes not require quintessence field.

1A similar RG improvement of black hole spacetimes can be found in (Bonanno & Reuter, 1999, 2000)


2.4 Laboratory of experimental astronomy and Solar

System physics

INAF Researchers: G.A. Baratta, G. Leto, M.E. Palumbo, G. StrazzullaUniversity Researchers: C. BlancoTechnical staff: G. Carbonaro, F. SpinellaPhD Students: O. GomisVisiting Students: M. LoefflerStudents: R. Brunetto, D. Gandolfi, S. Guglielmino

2.4.1 Background

Solid materials in space, namely ices, silicates and carbons, are present in different en-vironments such as the interstellar medium, comets, asteroids and outer Solar Systemobjects.

Refractory dust particles (average radius ∼0.05 µm) made of silicates or carbonaceousmaterial are released from stars (mainly in the red giant phase) in whose atmospheresthey are formed, into the interstellar medium (ISM). Occasionally diffuse clouds in theISM (nH∼1-103 cm−3, T∼100 K; where nH is the total number of H atoms, i.e. H+2H2,H2 being the numeric density of the hydrogen molecules) contract to form dense molecularclouds (nH≥104 cm−3, T∼10-20 K). In these regions the numeric density of dust particles(grains) is nd ∼ 10−12 nH . The temperature of the dust in dense clouds is as low as10-20 K and thus virtually all atoms and molecules (with few exceptions such as Heand Ne) that impinge on the grains stick on the surface to form ice mantles with anaverage radius estimated to be of the order of 0.1 µm. As the cloud contracts, atomichydrogen is converted into molecular hydrogen, through H+H combination on grains andthe consequent release of H2 in the gas phase. This process has important consequenceson the chemistry of icy mantles: when H dominates, hydrides species such as H2O, CH4,NH3, CH3OH are expected to form leading to a mantle dominated by polar molecules.When H2 dominates, molecules such as the observed CO and the inferred O2 and N2

accrete on grains to form an outer shell of apolar ices.The observation of protostars (still embedded in their placental cloud) is the mas-

ter probe of the presence of ices in the dense molecular clouds. In this case the almostblackbody continuum emitted from the young object is absorbed by grains whose temper-ature changes as a function of the distance from the object. These observations, mainlyobtained by IR spectroscopy, may reveal the evolution of ices due to thermal and/or en-ergetic processing (e.g. interaction with UV photons and/or stellar particle winds andcosmic rays).

Ices are also present on many objects in the Solar System such as the satellites of theexternal planets (Jupiter and beyond), the planet Pluto, the so called trans-Neptunianobjects (TNOs, a class of numerous small objects not yet well investigated), and comets.In this case the study of the composition of the ices is based on the study of the electro-magnetic radiation coming from the Sun and reflected by the surface of the object.

Energetic (keV-MeV) particles and UV photons impinging on solid surfaces made ofrefractory (carbonaceous and/or silicates) materials and/or ices are present in a varietyof environments in space including the interstellar medium and planetary system. Thestudy of the effects of ion irradiation and UV photolysis, based on laboratory simulations

LABORATORY OF EXPERIMENTAL ASTRONOMY 51

of relevant targets bombarded with fast charged particles and by Lyman-α photons underphysical conditions as similar as possible to the astrophysical ones, is the royal road tounderstand the evolution of interstellar medium and solar system objects. Two maineffects occur: (1) material is eroded from the target (sputtering) and (2) physico-chemicalmodifications are induced, including the formation of different molecules.

Fast ions, penetrating solids, deposit energy in the target by elastic interactions withtarget nuclei and by inelastic collisions causing ionizations and excitations. Thus chemicalbonds are broken along the path of the incoming ion and physico-chemical modificationsoccur, including the formation of molecules originally not present in the target. Thesemolecules include species that can be both more and less volatile than the parent ones.When carbon is an important constituent of the irradiated target it gives rise to a refrac-tory residue which is left over after warming up to room temperature. This residue hasa complex structure, and after prolonged irradiation evolves to form hydrogenated amor-phous carbon. In the case of UV photolysis, the energy is released to the target materialthrough single photo-dissociations, photo-excitations or ionization events per incomingphoton. Also in this case new molecular species are formed.

Different techniques have been used, by different groups, to characterize the chemistryinduced by energetic ions and UV photons. In our laboratory we have been using, forabout 20 years, in situ IR and Raman spectroscopy.

A number of different refractory materials (carbonaceous and/or silicates) and frozengases have been irradiated to study their chemical and/or structural evolution. Usu-ally samples are prepared at low temperature (10-20 K) and their spectral characteristicrecorded before, during and after processing with energetic ions (3 to 400 keV) and UVphotons (Lyman-α, 121.6 nm=10.2 eV). Targets are subsequently warmed-up and spectraare taken at increasing temperatures (20 to 300 K).

This research, in the past 20 years, has been financially supported by ASI, AssembleaRegionale Siciliana, CNAA, CNR, MIUR, OACt and University of Catania. In year 2003the research related to the 2002 successful MIUR-Cofin research proposal, coordinated byG. Strazzulla and involving also the experimental groups of Napoli (OA-Capodimonte)and Lecce (University), was still in progress. This proposal titled “Laboratory studiesof silicates present in the Solar System” is summarized in the section on “On going re-search” with a closer look to the role of Catania-LASp group. In 2003 under the PI-shipof S. Aiello (Florence Univ) a new research proposal was submitted and approved. Thelocal PI is G. Baratta and the project is a collaboration among researchers from manyitalian institutions: Universita degli Studi di Firenze, INAF-Osservatorio Astrofisico diCatania, Universita degli Studi di Messina, INAF-Osservatorio Astrofisico di Arcetri,INAF-Osservatorio Astronomico di Capodimonte Napoli, Universita degli Studi di Cata-nia, INAF-Osservatorio Astronomico di Cagliari, Universita degli Studi di Lecce. In the“On going research” section there is a more detailed description of the scientific objectivesof the Catania group.

2.4.2 Experimental facilities

2.4.2.1 The vacuum chamber

The in situ analyses are performed in a stainless steel high vacuum chamber (see rightpanel in Figure 2.37). Inside the chamber, in which pressure is kept below 10−7 mbar,


Figure 2.37: On the left side a schematic view of the experimental apparatus used for insitu Raman spectroscopy of ion irradiated samples is shown. On the right side details ofthe vacuum chamber in the “Raman configuration”. In order to obtain infrared spectrathe glass objective is removed. A hole in the sample holder allows the infrared beam totransmit through the substrate and the sample.

a substrate (crystalline silicon) is placed in thermal contact with a cold finger whosetemperature can be varied between 10 K and 300 K. A needle valve is used to admitpre-prepared gases (or mixtures) into the chamber, where they freeze on the substrate. AHe-Ne laser can be used to monitor the thickness of the ice film during accretion; this isachieved by looking at the interference pattern (intensity versus time) given by the laserbeam reflected at an angle of 45o both by the vacuum-film and film-substrate interfaces.Solid samples are simply mounted in thermal contact with the cold finger.

2.4.2.2 The ion implanter

The vacuum chamber is interfaced with an ion implanter (200 kV; Danfysik) from whichions with energy up to 200 keV (400 keV for double ionizations) can be obtained. Theion beam produces a spot of about 2 cm2 on the target and current densities are in therange of 10 nA cm−2 to a few µA cm−2. The amount of energy released to the icy samples(dose) is expressed in units of eV/16 amu and is calculated from the knowledge of the ionfluence (ions cm−2), the stopping power (eV cm2 molecule−1) of the chosen projectile, andits penetration depth or range in the target (molecules cm−2). The fluence is obtainedfrom a current integrator on the path of the ion beam, that measures the charge whichreaches the sample during irradiation; the other two parameters are well known and canbe provided by software such as SRIM. The penetration depth of 200 keV ions in the icy


Figure 2.38: Schematic description (not to scale) of three different types of experimentsperformed. The sketch on the left hand side refers to ion irradiation of icy films thinnerthan the penetration depth of impinging ions. In this case ions pass through the sample.The middle sketch refers to an icy sample irradiated during deposition. The process stopswhen the sample is as thick as required. The sketch on the right hand side refers toion irradiation of a sample thicker than the penetration depth of impinging ions. In thiscase, only the uppermost layers of the sample are irradiated. The ice underneath remainsunprocessed and ions remain implanted in the sample.

mixtures studied is about 0.2-2 µm. In order to have thicker irradiated samples, and thusspectra with a better signal-to-noise ratio, we have at times irradiated the icy mixturesduring deposition. In this case the dose is estimated from the knowledge of the depositionrate (molecules cm−2 s−1) previously calibrated, the ion flux (ions cm−2 s−1) and theenergy of impinging ions (eV). When irradiated samples are thicker than the penetrationdepth of impinging ions, the doses are given in units of ions cm−2. A schematic depictionof three different types of performed experiments is reported in Figure 2.38.

2.4.2.3 Upgrade and calibration of the ion implanter

The first part of the year has been dedicated to complete the calibration of the ionimplanter following the upgrading done in the last part of year 2002. A post-accelerationhas been settled in order to have ion beams up to 200 keV in case of single ionizationand 400 keV for double ionized ions. The new beam line has two main advantages. Firstof all the penetration depth (that is the range which ions travel in matter before beingstopped), which for a given material depends on the energy of impinging ions. Thus it isnow possible to irradiate thicker samples. This in turn means that it is possible to obtainspectra with higher signal to noise ratio and to detect weaker features in the spectra.

The total energy which ions release in the target per unit path length (also referredto as total stopping power) is given by the sum of the elastic and anelastic stoppingpowers. The relative amount of these contributions depends on the mass and energy ofimpinging ions. Thus the new beam gives us the possibility to span a larger range ofdifferent stopping power values allowing us to study those effects which depends on the


Figure 2.39: The new setup of the ion implanter of the Laboratory of ExperimentalAstrophysics at Catania Astrophysical Observatory. After the upgrade from 30 kV to200 kV the ion implanter is shielded with a conductive wall. All instruments and controlsystems are placed out of the restricted area where the beam is accelerated.

specific interaction (elastic versus anelastic) of ions with matter. A view of the setup ofthe upgraded implanter is shown in Figure 2.39.

Most of the experiments performed during 2003 have extensively used the new im-planter capability giving rise to new or better determined experimental evidences. Allthe measurement subsystems that are described in the following have been accuratelyrecalibrated and, in most cases, are already used in the new setup.

2.4.2.4 The UV lamp

A hydrogen microwave discharge resonance lamp (Opthos Instruments) is interfaced withthe vacuum chamber through an MgF2 window; from this lamp 10.2 eV (λ=121.6 nm)photons are obtained. An aluminium light collector is placed at the end of the lamp inorder to increase the number of UV photons which reaches the sample. A light detector,placed at the end of the aluminium light collector, is used to measure the UV flux duringphotolysis. The detector is a platinum wire which gives a current, by the photoelectriceffect, proportional to the UV flux. The UV flux is perpendicular to the sample holderand forms an angle of 45o with respect to the ion beam. This gives the unique opportunityto simultaneously process the samples with ions and UV photons.


2.4.2.5 Infrared transmittance and reflectance spectroscopy

Infrared spectra are obtained by a Fourier Transform Infrared (FTIR) spectrometer(Bruker Equinox 55). The sample holder has a hole, with a diameter of 4.5 mm, whichallows the infrared beam to transmit through the substrate and the sample. The infraredbeam forms an angle of 45o with both the ion beam and the substrate holder. Thus, spec-tra can be taken in-situ before, during, and after irradiation, without tilting the sample.By illuminating the sample with an external light source it is also possible to performreflectance spectroscopy in the 0.65-2.5 µm range. Measures in the 0.4-1 µm spectralrange can be obtained with the CCD detector and the Triplemate SPEX spectrometerdescribed below.

2.4.2.6 Raman spectroscopy

Figure 2.37 schematically shows the arrangement used to acquire Raman spectra. A con-tinuous Ar-ion laser beam (λ=514 nm) enters a confocal illuminator perpendicularly toits optical axis, into which it is deflected by a microprism. The confocal optical system isarranged in such a way that any parallel beam incident along the optical axis in the oppo-site direction of the laser is focused onto the entrance slit of the spectrometer (TriplemateSPEX). By means of two flat mirrors, the laser beam is reflected towards the vacuumchamber, where it is focused on a 40 µm spot on the sample. The same objective whichfocuses the laser beam on the sample collects the Raman-scattered light, which reaches theconfocal illuminator going back along the same path of the laser beam. This confocal sys-tem makes it possible to obtain Raman spectra of samples located several meters far fromthe spectrometer with negligible performance losses. The substrate holder is mounted atan angle of 45o both with the ion beam and the Ar-ion laser beam. This configurationoffers the advantage that spectra can be easily taken in situ, even during irradiation withions or UV photons, without tilting the sample. The system is equipped with a CCDdetector which can be used for reflectance measurements in the 0.4-1 µm range as well.

2.4.2.7 Photo and ion luminescence

During year 2003 a photoluminescence facility has also been implemented. Photolumi-nescence spectra can be obtained in situ. For this purpose, an UV exciting radiation(Nd-YAG laser at 266 nm) is used. The UV laser enters the chamber through a sap-phire window and is focused on the sample at a normal incidence angle. Luminescenceinduced in the sample by ions during irradiation (ion-induced luminescence) can be alsoinvestigated.

2.4.3 Results

The main results obtained during this year are here summarized.

2.4.3.1 Ion irradiation and UV photolysis of ices

The effects induced by fast ions and UV photons on astrophysical relevant ices have beenseparately studied in different laboratory for several years. It is well known that both pro-cesses induce chemical and structural modifications of the ice sample. However only few


laboratories have the capability to study both effects with the same experimental set-up.Leto and Baratta [34] have continued their study on the comparison of the effects inducedby energetic ions and UV photons on simple ices. They performed an experimental studyon the structural effects induced by Lyman-α photons in crystalline water ice carried outby in situ infrared spectroscopy of the water ice stretching band at 3 µm. They foundthat, as already observed in the case of processing with energetic ions, Lyman-α photonsare able to fully amorphize the crystalline water ice structure after a dose of few eV permolecule. They performed a detailed comparative study of the evolution of the samplesduring UV photolysis with ion irradiation experiments with 30 keV H+, 30 keV He+ and60 keV Ar++ (see Figure 2.40).

Figure 2.40: Amorphization of Ic water ice at 16 K by UV-photons or ion irradiation: leftpanel shows the evolution of the Ic ice stretching band under UV photolysis, right panelthe evolution due to 30 keV He+ irradiation.

The analysis included the study of peak position, band area and amorphous vs crys-talline content evolution of the sample with irradiation dose. They demostrated that thetwo processes follow the very same path and the needed energy to complete the crys-talline to amorphous transition lies within a factor 2 in all the studied cases (2-4 eV permolecule).

2.4.3.2 Nitrogen condensation on water ice

Most of the studies relative to water diluted in different icy matrices have been performedin the mid-infrared spectral range where fundamental vibrational modes are present.Palumbo and Strazzulla [40] have perfomed a new experimental study meant to investigatethe spectral characteristics in the near-infrared of N2:H2O icy mixtures and samples of N2

diffused in water ice. This spectral range, typical of combination and overtone modes, isrelevant to study objects in the Solar System. As a matter of fact, based on observationsin the 0.5-2.5 µm (20,000-4,000 cm−1) spectral range, the surfaces of the planet Pluto, ofthe major Neptune’s satellite Triton, and possibly of a number of small trans-Neptunianobjects, seem to be dominated by frozen nitrogen mixed with small amount of methane,carbon monoxide and dioxide, and water. Due to climatic cycles volatile species, such asN2, are expected to sublimate and recondense on the surface while less volatile species,such as H2O, remain segregated on the surface. Although water easily segregates because


its vapor pressure is so different from that of the dominant nitrogen, it cannot be excludedthat a small quantity of water molecules can be trapped in nitrogen ice. This could bethe result both of a recondensation process of nitrogen from the atmosphere on a water-rich surface patch and of the condensation of the dominant nitrogen along with a smallamount of water vapor, not yet detected, but likely present, in the tenuous atmosphere ofPluto and Triton. Laboratory experiments have shown that when water is highly dilutedin nitrogen a feature at about 5300 cm−1 (1.88 µm) appears. Palumbo and Strazzulla [40]suggest that this band should be searched for on these objects.

2.4.3.3 C70 fullerene

C70 fullerene films deposited on a silicon substrate have been bombarded with He+ ionsat 30 keV at room temperature under vacuum. The structural changes undergone byC70 have been followed by both FT-IR and Raman spectroscopy. The results have beencompared by Cataldo et al. [11] to the behavior of C60 fullerene obtained previously bythe same authors and discussed in an astrochemical context. The main conclusion is thatC70, contrary to C60, does not form oligomers at low radiation dose but it is directly andgradually degraded to amorphous carbon (carbon black).

2.4.3.4 Carbon and nitrogen implantation on icy surfaces

Solid surfaces of atmosphereless objects in the Solar System are continuously irradiated byenergetic ions (from solar wind and flares, planetary magnetospheres, and cosmic rays).Reactive ions (e.g., H, C, N, O, S) induce all of the effects of any other ion includingthe synthesis of molecular species originally not present in the target. In addition, theseions have a chance, by implantation in the target, of forming new species containing theprojectile. An ongoing research program performed at the Catania LASp laboratory aimsat investigating the implantation of reactive ions in many relevant ices (and mixtures) byusing IR spectroscopy. Strazzulla et al. [46] presented new results obtained by implantingcarbon and nitrogen ions in water ice at 16 and 77 K. Carbon implantation producescarbon dioxide and the production yield has been measured. Nitrogen implantation doesnot produce any N-bearing species detectable by IR spectroscopy. Both ions are alsocapable of synthesizing hydrogen peroxide (H2O2) at the two investigated temperatures.Strazzulla et al. [46] also showed that, although a relevant quantity of CO2 can be formedby C implantation in the icy Jovian moons, this is not the dominant formation mechanismof carbon dioxide.

2.4.3.5 Frozen hydrocarbons

Baratta et al. [3] have irradiated CH4-containing icy mixtures, with 60 keV Ar++ ions at12 K to investigate the formation of new molecules and the development of a refractoryresidue. Recent observations have shown that the surfaces of some objects in the outerSolar System, namely Pluto, Triton, and possibly a number of small trans-Neptunianobjects, are dominated by frozen nitrogen mixed with small amounts of methane, carbonmonoxide and dioxide, and water. Many other, even more complex, molecules could bepresent as well, although not yet firmly identified. Even if molecular nitrogen is the mostabundant species on the surface of Pluto, the presence of regions rich of methane has beensuggested. On the other hand the spectrum of Triton is compatible with the presence of


regions with water and carbon dioxide spatially segregated. Furthermore, due to planetaryclimatic cycles, volatile species sublimate and recondense in a complex manner. Previouslaboratory work has concentrated on the study of the effects of ion irradiation of pureCH4, and N2 rich mixtures with H2O and CH4 as minor components. Baratta et al. [3]have analysed mixtures where water, methane and nitrogen are in comparable amountand that could be relevant to “simulate” those superficial patches where segregation istaking place. Laboratory experiments have shown that several molecules containing cyano(CN) groups are formed after ion irradiation at low temperature. These findings are ofprimary relevance because of their role in the development of a very complex chemistry.These molecules could have been delivered by comets on the primitive Earth during theearly heavy bombardment. Here, they could have contributed to the development of morecomplex biogenetic compounds.

2.4.3.6 Evolution of the surface materials on Trans Neptunian Objects: therole of ion irradiation

Cosmic ion irradiation is believed to be one of the processes driving the evolution of thesurface materials on TNOs. In their review paper Strazzulla et al. [45] summarized thelaboratory simulations of radiation effects induced in likely TNO materials. In particularthe production of new molecular species, the formation of refractory organics, and thespectral changes induced in icy targets and in natural bitumens have been described. Inorder to establish if the effects seen in the laboratory are in fact responsible for the surfaceproperties of the TNO’s, the present knowledge of the ion fluxes is necessary. For objectsat selected solar distances they calculated dosage time vs depth into the material. Assuggested by recent experiments, the contribution of the electronic energy loss and thatdue to knock-on collisions have been given separately. The relevance of ion-irradiation forthe physico-chemical properties of TNOs has been demonstrated, and the need for futureinvestigations has been outlined.

2.4.3.7 Understanding the origin of the interstellar 3.4 µm band: new labo-ratory striking results

Carbon grains in the interstellar medium evolve through exposure to UV photons, heat,gas, and cosmic rays. Understanding their formation, evolution, and destruction is anessential component of evaluating the composition of the dust available for newly formingplanetary systems. The 3.4 µm absorption band, attributed to the aliphatic CH stretchvibration, is a useful probe of the degree to which energetic processing affects hydrogenatedcarbon grains.

Mennella et al. [36] reported on the effects of ion bombardment of two differentkinds of nano-size hydrogenated carbon grains with different hydrogen content. Grainsamples, both with and without a mantle of H2O ice, were irradiated with 30 keV He+ tosimulate cosmic-ray processing in both diffuse and dense interstellar medium conditions.The ion fluences ranged between 1.5×1013 and 7.9×1015 ions cm−2. Infrared and Ramanspectroscopy were used to study the effects of ion irradiation on grains. In both thedense and diffuse interstellar medium simulations, ion bombardment led to a reduction ofthe 3.4 µm band intensity. To discuss the effects of cosmic-ray irradiation of interstellarhydrogenated carbon materials they adopt the approximation of 1 MeV monoenergetic


Figure 2.41: Time evolution under dense ISM conditions for hydrogenated carbon grainswith an initial degree of hydrogenation as determined by processing in the diffuse ISM [36].The time t = 0 corresponds to the conditions for which hydrogenation of carbon grainsis inhibited. The different curves represent the evolution for grains at different depths(AV ) inside the cloud. The thick line refers to the evolution if Galactic UV processingwere absent. The horizontal line represents the hydrogenation degree corresponding tothe most stringent upper limit for the destruction of the 3.4 µm band in dense regions.

protons. An estimate of the CH bond destruction cross section by 1 MeV protons wasmade based on experiments using 30 keV He+ ions and model calculations. In combinationwith results from their previous studies, which focused on UV irradiation and thermal Hatom bombardment, the results obtained indicate that the CH bond destruction by fast-colliding charged particles is negligible with respect to that of UV photons in the diffuseISM. However, in dense cloud regions, cosmic-ray bombardment is the most significant CHbond destruction mechanism when the optical depth corresponds to values of the visualextinction larger than ∼5 mag (see Figure 2.41). The results presented by Mennella etal. [36] strengthen the new interpretation of the evolution of the interstellar aliphaticcomponent (i.e., the CH bonds in the CH2 and CH3 groups) as evidenced by the presenceof the 3.4 µm absorption band in the diffuse medium and the absence of such a signature inthe dense cloud environment. The evolutionary transformation of carbon grains, inducedby H atoms, UV photons, and cosmic rays, indicates that CH bonds are readily formed, insitu, in the diffuse interstellar medium and are destroyed in the dense cloud environment.

2.4.3.8 Asteroids photometry

After the characterization of the CCD Kodak KAF 42202, 2048x2048 µm pixel-size (seeReport 2001) and the mounting of the Johnson BVRI filter system, the construction ofthe camera, to be mounted on the Schmidt 41/61 telescope at the M.G. Fracastoro stationof the Catania Astrophysical Observatory, has been completed. Since the mechanical ren-ovation has not been completed, the camera has been mounted and tested on the Schmidt67/92 telescope of the Asiago Observatory where it started operating during the night of


the 23rd March 2003. The observing campaign of the globular cluster M13 and of thegalaxies M51 and M101 has continued up to the 8th April 2003. The asteroid 1727 Mette,due to its dim magnitude and the uncertain rotational period value, has been selectedas a target of the photometric measurements. Some problems with the motion of thefilters carrier “guide bearing” have hampered the rapid observation with different filters.Since the camera need to be focused at every filter change, the same filter has been usedfor each observing night. Nonetheless two complete lightcurves in the V band and threecomplete lightcurves in the R band of the 1727 Mette have been obtained thus allowingto compute a more accurate rotational value than that reported in the literature. Thereduction of the CCD images has been carried out with IRAF standard routines and withthe Source Extractor, a software realized for the images processing (Bertin and Arnouts1996). For the computation of the rotational period the Fourier analysis has been applied,as already done in our previous papers. The results have been presented at the V Con-vegno Nazionale di Scienze Planetarie, held in Gallipoli in Sept 2003 [132]. References:Bertin E.., Arnouts S.: 1996 Astron. & Astrophys. Suppl. Ser. 117, 393;

2.4.3.9 On going research

“Laboratory studies of silicates present in the Solar System” (financed by MIUR, Cofin-2002, P.I. G. Strazzulla, INAF-Catania Astrophysical Observatory). The study of theformation and evolution of different classes of solid bodies in the Solar System is one of themost relevant and puzzling subjects of modern planetology. Silicates, carbons and ices arethe main components the solid objects in the Solar System are made of. The Italian groupsat Catania, Lecce, and Napoli are involved in a wide variety of laboratory experimentsaimed at simulating materials and/or processes occurring in space and appropriate togain information on material properties in a wide set of space environments.

The main role that the Catania-LASp group is playing in this research is the studyof the spectral properties of the chosen silicates during and after processing with UVphotons and energetic ions. UV irradiation and ion bombardment will be performed toinvestigate in situ, at low pressure and at different temperatures, some key aspects:

• amorphysation induced on crystalline silicates and changes in the chemical compo-sition (stoichiometric ratios). The technique used in situ will be IR transmissionspectroscopy (IR band shapes are sensitive to the structure of silicates) [52; 4];

• thermal annealing of silicates amorphised by ion irradiation to compare their crys-tallisation temperatures with those of amorphous synthesised samples [4];

• ion irradiation of albite and nepheline: study of the species released in the gas phaseand changes in the chemical composition of the irradiated surfaces;

• implantation of reactive ions (H, C, N, O, Na) in silicates: do new chemical speciesthat include the projectile form?

• during the irradiation experiments in situ diffuse reflectance spectroscopy in the0.6-2.5 µm range will be performed to study, in particular, the spectral slope to becompared with those observed in astronomical objects;


• some silicate samples will be coated with layers of organic matter (e.g. producedby depositing frozen hydrocarbons and irradiating them) and irradiated to study bydiffuse reflectance spectroscopy in the 0.6-2.5 µm range the variation in the spectralslope;

• some silicate samples will be coated with layers of water ice and irradiated to in-vestigate the possibility of hydration via intermixing and back-diffusion of waterfragments e.g. H, OH, O.

“Comparison of the effects of ion irradiation and UV photolysis on astrophysical rel-evant ices deposited on both inert and active substrates” (financed by MIUR, Cofin-2003,P.I. S. Aiello, Florence Univerity). As said above solid objects in space are continuouslyexposed to energetic processes such as cosmic rays and UV photons. Although the effectsinduced by such physical agents have been separately studied in different laboratories forseveral years, only recently a detailed comparison of the effects induced by fast ions andUV photons has been carried out using the same experimental set-up. There is no ex-haustive study of their possible combined (synergic) effects on astrophysical relevant pureices or mixtures. In addition, most of the studies of the effects induced by ion irradiationand UV photolysis on ices from our and other groups have concentrated on ices accretedon flat surfaces such as silicon crystal, KBr and CsI. These experiments have been and arenecessary as a starting point in the study of the effects induced by UV photons and fastions. However, in space ices accrete on different surfaces such as carbons and silicates.In several instances the interaction between the ice and the surface underneath cannotbe neglected. As example by acting as a different catalytic surface, carbons and silicatesgrains could determine a different chemical evolution of the irradiated ice mantles presenton them. The research on this field will follow two main lines: i) The experimental studyof the combined effects induced by ions and UV photons in frozen gases. ii) Using re-alistic astrophysical substrates (i.e. amorphous carbon grains and silicates) the role ofthe substrate in determining a possible different chemical evolution of the ion and/or UVprocessed ice will be investigated.

a) Experimental study of the combined effects induced by ions and UV photons infrozen gases.

It has been shown that ions and UV photons can produce a different chemical evolutionin the irradiated ice, where the differences observed have been interpreted as due to thedifferent way in which ions and UV photons release energy to the target. Anyway fastions and UV photons are both present in space, so any combined (synergic) effects shouldbe considered. The effects induced by ions or UV photons could be enhanced or depletedand new effects could appear if the sample is simultaneously irradiated (or has beenalready irradiated) with UV photons or ions respectively. It will be investigated if anysynergic effect between fast ions and UV photons occurs in N2 containing ice mixtures,in particular:

Solid phase N2 is expected to be present in ice mantles on interstellar grains (T below30 K), although the chance of a direct IR detection are low due to the N2 band’s intrinsicweakness. It has been reported that ion irradiation of pure N2 and N2 rich ice mixturesleads to the formation of the N3 radical, while no N3 was observed after UV Lyman-alphaphoton irradiation of the same ice mixtures. These results have been interpreted as dueto the inability of UV Lyman-alpha photons to dissociate N2 and produce N atoms andcould be used to distinguish between ion irradiated and UV photolyzed interstellar grains.


A combined irradiation experiment will be performed with fast ions and UV Lyman-alphaphotons of ice mixtures containing N2, in this case the availability of N atoms given byion irradiation could give the possibility to UV photons to form radicals or molecules (i.e.N3, XCN) not otherwise obtainable. The chemical evolution of the irradiated ices will befollowed by in situ IR and Raman spectroscopy.

b) Fast ion and UV processing of ices deposited on astrophysical relevant substrates.

Fast ion and UV processing of ices deposited on a substrate can lead to the formationof species that contain both the ice and the substrate atoms. This can be either due tothe layers mixing determined at the interface by the recoil atoms (mostly observed forfast ions) or to the radicals formed in the ice nearby the interface (or that diffuse to theinterface) that react with the substrate atoms (UV photons and fast ions). In this researchproject we plan to study the formation of species at the interface between astrophysicalrelevant ices and substrates. In particular:

In collaboration with the research unit of the Astronomical Observatory of Capodi-monte (Napoli) a study will be performed of the species formed at the interface by ionirradiation on amorphous carbon grains covered with water ice and with different kind ofices containing O and/or N atoms (i.e. H2O, N2, O2). The species formed at the interfacewill be studied by in situ IR and Raman spectroscopy and will be easily distinguishablesince they will contain carbon atoms (i.e. CO2, CO). The efficiency that this formationprocess has in astrophysical environments will be evaluated. Successively UV Lyman-alpha photolysis experiments will be carried out on the same ices deposited on analogoussubstrates; the species formed by Lyman-alpha photons and their efficiency of formationwill be compared with those obtained for fast ions.

Calcite (CaCO3) has been recently discovered in the solar type protostar NGC1333-IRAS-4 and in two planetary nebulae. These observations represent the first detection ofcalcite outside the Solar System. Since, obviously, no liquid water is present in such ob-jects, the calcite could not be formed through weathering of silicates in a watery (CO3)2−

solution as commonly believed for the carbonates observed in Solar System bodies. It hasbeen suggested that the calcite observed in IRAS-4 formed through processing of CO2

and H2O containing ices on Ca containing silicates. In particular it has been indicated,as a possible source of processing, the X-rays heating from the central star. Once a hardX-ray hits a grain it can warm up the grain locally, the mobility acquired by the water iceenriched in CO2 should allow the ice to react with the Ca2+ contained in the silicate latticeto form calcite. Another possible mechanism involves energetic ions (i.e. from flares inIRAS-4) that could induce calcite formation at the interfaces between ices and silicates.In particular it will be performed ion irradiation and UV photolysis experiments on H2Oand CO2 ice mixtures deposited on Ca containing silicates (i.e. diopside), the possibleformation of calcite will be followed by in situ IR and possibly Raman spectroscopy, theefficiency that this process has in astrophysical environment will be evaluated.

Sulfur is depleted from the gas phase in cold dense molecular clouds. Anyway theabundance of the sulfur-bearing species that have been observed in the solid phase (i.e.OCS, SO2, H2S) is not able to account for the cosmic S abundance; this matter has beenknown for a long time as the missing sulfur problem. Recently FeS has been discoveredin the infrared spectra of young stellar objects. The FeS grains have been found to be animportant but previously unrecognized component of circumstellar dust. The abundanceof sulfur found in FeS grains should be consistent with the depletion of sulfur from the gasphase and should solve, according to the authors, the missing sulfur problem. The LASp

LABORATORY FOR DETECTORS 63

group will investigate a possible FeS formation mechanism in dense molecular clouds. Inparticular irradiation experiments on iron-containing substrates (i.e. silicates) coveredwith ices containing sulfur bearing-species (i.e. SO2) will be carried out to see if FeS canbe formed at the interface.

2.4.4 Workshops and meetings

• Gas phase formation and destruction of carbon based nanoparticles, Saint Jacut dela Mer, France, 28-30 January 2003

• Processed Solids in Astrophysics (PROSA), Lecce, 20-21 February 2003

• First decadal review of the Edgeworth-Kuiper Belt, towards new frontiers, Antofa-gasta, Cile, 11-14 March 2003

• EGS-AGU-EUG Joint Assembly, Nice, France, 6-11 April 2003

• Solid state chemistry in star forming regions, Leiden, NL, 14-17 April 2003

• Spectroscopy of partially ordered macromolecular systems, Prague, Czech Republic,21-24 July 2003

• V Convegno Nazionale di Planetologia, Gallipoli (Lecce), 15-19 Settembre 2003

• Interdisciplinary meeting on polyynes and carbyne, Napoli, 30-31 October 2003

• The third european workshop on exo/astrobiology. Mars: the search for life, Madrid,Spain, 18-20 November 2003

2.5 Catania astrophysical Observatory Laboratory for

Detectors (COLD)

INAF Researchers: G. Bonanno, R. Cosentino, S. ScuderiStudents: D. GandolfiTechnical Staff: M. Belluso, P. Bruno, A. Calı, M.C. Timpanaro

The Catania astrophysical Observatory Laboratory for Detectors (COLD) has beenactive in the development of astronomical technology since the end of the 80s. The mainfields of expertise of the group include:

• Development, realization and test of electronics based on programmable and notprogrammable logic.

• Development, realization and test of detectors cameras

• Automation and controls software and hardware for astronomical instrumentation

• Detectors characterization


The exploitation of this expertise has brought the group to be heavily involved in sev-eral projects and activities on the characterization and development of detectors for UVand optical astronomy, and in the development and realization of astronomical camerasand instruments. Educational activities through high school and university courses, stu-dent and PhD training and technological transfer to industry are fundamental activitiesof the group. Last but not least the group gives technological support to astronomicalobservations both at the Catania Astrophysical Observatory and at the Italian NationalTelescope Galileo.

To comply with all these activities the group has available several technical resourcesand experimental facilities which, in particular, include:

• Calibration facility for electro-optical characterization of detectors

• Mechanical Workshop

• Electronics Laboratory

• Clean room (12 squared meters, class 100)

The results of the activities carried out in 2003 can be summarized as follows:

2.5.1 Detectors

2.5.1.1 CCD controllers

The new generation CCD controller is an improvement of the CCD controller in use atTNG. A new interface with the host computer, based on a high-speed link and PCI board,able to sustain high data transfer rate has been designed and built. The sequencer hasbeen modified in order to improve high-speed clocks and different reading modes. A newanalogue board based on a fast ADC’s and new signal processing has been designed. Theboard is able to process four channels simultaneously allowing high acquisition rates.The development of this CCD controller is done in collaboration with the INAF - Astro-nomical Observatory of Padua and the SkyTechnologies firm.During the past year the new digital board has been intensively tested with the oldanalogue board and several CCDs. The tests have been successful so the entire system(new analogue board) is now under test to optimize the read-out noise performances withCCDs. Furthermore a stand alone software based on Visual C++ has been developed tomanage completely the CCD controller.

2.5.1.2 CVD Diamonds detectors

The use of polycrystalline CVD diamond for the detection of ionising radiation (includingUV and X-ray) has been widely reported. These results highlight the advantages of dia-mond as a radiation-hard material with exceptional thermo-mechanical properties. Theimportance of material quality in device performance has also been reported. Because ofadvances in CVD synthesis technology the electronic properties that are currently achievedin polycrystalline CVD diamond rival some of the best results obtained with single crystalnatural diamonds. It is important therefore to attempt to characterize the quality of thematerial in addition to device performances.


Figure 2.42: The 5×2 CVD diamond matrix

The project has received fundings by CNAA, MURST, and ASI and is carried out incollaboration with the Dipartimento di Astronomia e Scienza dello Spazio of the Univer-sity of Florence, the Dipartimento di Meccanica e Materiali of the University of ReggioCalabria and the Dipartimento di Ingegneria Meccanica of the University of Rome (TorVergata).In the past year the team has worked to the development and the characterization oftruly 2-D imaging devices. A 2×5 pattern of square pixels(fig.2.42), consisting of couplesof planar gold contacts separated by a 20 µm open gap, has been deposited on the as-grown surface of high quality CVD diamonds. The size of each pixel is 85 µm and thepitch is 70 µm. The pixels are bonded on a printed circuit to readout the signal with aspecifically designed electronics. Initially, an assessment of the film quality was carriedout using micro- and macro-Raman spectroscopy and low-temperature UV photolumines-cence. Then, electrical and photoconductive properties of the imagers were characterized.The devices were irradiated with visible, UV, and soft-X ray photons (30-1100 nm) to an-alyze their performance in terms of spectral and time response. In particular, the spatialuniformity of the locally photo-induced electrical conductivity and the cross talk betweenadjacent pixels were studied through a 2-D mapping of the imager surface as a functionof applied electric field and photon penetration depth.

2.5.1.3 SPAD detector

SPAD is a p-n junction biased above the breakdown. In this operative condition a hole-electron pair, generated in the depletion layer causes an avalanche, measurable as a cur-rent. The diode works as a single photon detector with an infinite gain. The current flowsin the diode until the drive circuit, called active quenching circuit (AQC), turns off thepolarization for a dead time, defined hold off time, and then restores it. In this way theSPAD is ready for another event. This turn off time depends on the quality of the SPAD.This activity is carried out since 2001 in collaboration with R&D office of ST Microelec-tronics (STM).In the past year we have developed, realized and tested an active quenching circuit to


drive a single SPAD detector. The main characteristic of the circuit is its acquisition ratethat reaches an upper value of 400000 event/s.Furthermore we have started a new project in collaboration with several scientific in-stitutions (INFN, IMM-CNR and the University of Catania) and industries (STM andSilena International) to develop a camera based on a SPAD array which will be usedfor different scientific and industrial applications. The COLD group will be responsiblefor and participate in the characterization of the detector, the development of the front-end electronics, the development of the active quenching circuit, and the development ofcontrol software. The final product will be tested at the 91cm telescope of the CataniaAstrophysical Observatory.

2.5.2 Telescopio Nazionale Galileo

The group has been involved since the beginning in the Galileo project participating inthe realization of the SARG high resolution spectrograph and being responsible for allthe CCD cameras of the telescope. The activities carried out in the past year are:

2.5.2.1 Maintenance and upgrade of TNG CCD controllers

Together with the ordinary activity of maintenance to guarantee the normal standardof efficiency of the CCD controller present at the TNG, we have started the process ofupgrade of the CCD controller. In particular we have successfully tested at the telescopean autoguide system using an hybrid controller (that is, based on the new architectureapart from the analogue board). Also, to comply with the TNG standards the softwareto run the new CCD controller is being developed using Visual C++ and Java.

2.5.2.2 Development and maintenance of TNG user interfaces

Exploiting the experience built during the SARG project the group has started to work onthe maintenance and upgrade of the Graphic User Interfaces (GUI) of the telescope andinstruments written in IDL in collaboration with the TNG team. In the past year variousmodifications and improvements have been done on the GUIs of the High ResolutionSpectrograph (SARG), the low resolution spectrograph (LRS), the telescope trackingsystem and the derotator system. Among these activities there is also the realization ofa new exposure time calculator (Java based) for SARG.

2.5.3 Participation in National and international projects

We have already described in a previous section the activity of the group in the TNGproject. During 2003 the group has also been working on two international projects: theESA Eddington satellite and the ESO XSHOOTER spectrograph.

2.5.3.1 Eddington project

Eddington is an ESA satellite devoted to the search for habitable planets and the mappingof stellar interiors. The project has been cancelled during 2003 by ESA SPC due tofunding problems. Nevertheless the CCD activity is still going on and ESA has committeditself to conclude it. The CCD contractor (the E2V) has already delivered the CCDs to


Figure 2.43: The CCD camera for the Schmidt telescope mounted at Cima Ekar

the Eddington Project Office at ESA. The COLD group participates in the activitiesconcerning the evaluation, the screening and the characterization of the CCD chips. Thedelivery to our group of one of Eddington CCDs is foreseen for the first half of 2004.

2.5.3.2 XSHOOTER Spectrograph

X-shooter is a wide-band, high-efficiency, intermediate-resolution spectrograph for theCassegrain focus of one of the 8m Unit Telescopes of the VLT. It consists of three armswith optimized optics, coatings, dispersive elements and detectors. It is designed tooperate at spectral resolution R = 5000 - 10000, depending on wavelength and adopted slitwidth. X-shooter is a European Consortium with five partners, Denmark, Italy, France,the Netherlands and ESO. The spectrograph is under construction after the approvalby ESO in 2003. Our group will cooperate with ESO in the characterization of theoptical detectors system and will participate in the integration of the visible arm of theinstrument.

2.5.4 The CCD cameras for Catania Astrophysical Observatory

2.5.4.1 CCD camera for the Schmidt telescope

The camera for the Schmidt telescope at SLN has been completed at the beginning of theyear and has been tested at the Schmidt Telescope at Cima Ekar (fig. 2.43). In particular,the camera saw the first light on march 28th 2003, then it was used until 10th of April for


Figure 2.44: The prototype of the CCD camera for the 91 cm telescope

multiband photometric observations of the asteroid 1727 Mette and observations in theR filter of a newly discovered variable stars of the type W Ursae Majoris.

2.5.4.2 CCD camera for the 91 cm telescope

The camera for the 91 cm has been designed in collaboration with a local firm (HITEC)and realized by the same firm. The camera prototype (see fig.2.44) has been alreadymanufactured and in the past year has undergone several vacuum leak and cryogenicstests. The first test with CCD under operating conditions are foreseen for the first monthsof 2004.

2.5.4.3 Support to solar and stellar observations

The group is involved in the improvement of the performances of the instrumentation forsolar and stellar scientific observations. In particular we are in charge for the maintenanceof hardware and software of all scientific CCD cameras and controllers.

2.5.4.4 Collaboration with Industries

As the development of new technology is a fundamental activity of our group the inter-action with industries is strategic for the fulfillment of this objective. The most recentexamples of projects developed in close collaboration with industries are: the SPADproject which is being realized with ST Microelectronics, the CCD controller project withSkyTechnologies and the CCD camera for the 91cm telescope at Serra La Nave realizedtogether with HITEC.

2.6. COMPUTATIONAL TECHNOLOGIES FOR ASTROPHYSICS 69

Figure 2.45: (left panel) IBM SP 9076. (right panel) IBM p650 Series.

2.6 Computational technologies for astrophysics

INAF Researchers: V. Antonuccio, U. BeccianiPost Doc.: A. GermanaPhD. Students: D. Ferro, A. RomeoFellow: M. ComparatoTechnical Staff: A. Costa, E. Martinetti

2.6.1 Introduction

The development of high performance computing gives a fundamental improvement to thestudy of the origin and the evolution of the Universe. This leads to the study of complexscientific problems, generally using parallel algorithms on massively parallel systems MPPand SMP systems. However, the availability of these resources produces a large amount ofdata that the research needs to manage and analyze. At present, computational resourcesneeded to run large simulations are available only either in high performance computingsites or using distributed resources. Catania Astrophysical Observatory has two IBM SMPsystems: the IBM SP 9076, with 24 processors and 48 Gbyte RAM memory (Fig. 2.45,left panel) and the IBM p650 Series, with 8 processors and 16 Gbyte RAM memory (Fig.2.45, right panel) principally used for cosmological simulations. This system enables to runvery large parallel programs and some parallel codes have been developed by researchers.

The problem of the data analysis is also a fundamental task of this group, that isinvolved in a European project for data analysis using the scientific visualization. As-troMD manages multidimensional data from cosmological simulations, but it can alsomanage data from observational surveys. The study and the development of gravitationalN-body codes using parallel computing techniques is in progress. The tree code has beenimplemented on three platforms (T3E, Origin and SP) using the IBM SP system ac-quired by Catania Astrophysical Observatory. The new final version FLY (Fast Leveled


tree n-bodyY code) (http://www.ct.astro.it/fly/) has been made accessible to the public(public domain) and it was recently included in the Computer Physics CommunicationsProgram Library. The project of data analysis and visualization, proposed by the CataniaAstrophysical Observatory and by CINECA for the years 2001 and 2002 was financed byCNAA, for the preliminary studies. It will consist in testing some useful techniques and indeveloping a package of scientific visualization AstroMD (http://www.cineca.it/astromd)whose first open source version is already available. The package, AstroMD, is basedon the Visualization Toolkit (Kitware), which is a software object-oriented to 3D graph-ics. AstroMD performs the multi-dimensional and multi-varied analysis, contains sometools that can visualize clusters, computes specific quantities (i.e. Correlation functions,Minkowski functionals etc..), analyzes vector fields and uses the IVR (Immersive VirtualReality) techniques. The development of AstroMD has been further financed (Sept. 2001- Nov. 2003 ) by the European Community which has approved the Cosmo.Lab project(Gheller et al. 2002, http://cosmolab.cineca.it). The results have been presented at sev-eral conferences.The INAF-Catania Astrophysical Observatory, through an agreement with the INFN (Na-tional Institute for Nuclear Physics), has realized a Data Grid node site in our institute.This node is already running in the INFN grid, and will be a node of the first Italian Gridfor Astrophysics following the international standards in this field.During the year 2003, in collaboration with the University of Roma La Sapienza andENEA Casaccia, we have completed the activity Astrocomp, a portal for astrophysical sim-ulations on a grid of Supercomputers financed by the CNR Agenzia 2000 (http://www.astro-comp.it) The project was developed in the period 2002-2003. The idea at the basis ofour project is to create a national and European portal which allows to create a reposi-tory of easily usable computational codes and a common data base to be made availableto the entire national (and international) community. The original characteristic of theproject is that, thanks to the synergy among the different research units participatingto the project, it will allow to share a large, distributed virtual computational resourceassembled by the different platforms made available. More details on these projects arereported in the following paragraphs.

2.6.2 FLY. A parallel tree N-body code for cosmological simu-lations. A Public Domain code.

FLY was recently included in the Computer Physics Communication Program Library[2]. It is a parallel collision-less N-body code which relies on the hierarchical oct-treedomain decomposition introduced by J. Barnes & P. Hut (1986) for the calculation of thegravitational force. FLY is a parallel treecode which makes heavy use of the one-sidedcommunication paradigm to handle the management of the tree structure. In its publicversion the code implements the equations for cosmological evolution, and can be run fordifferent cosmological models.FLY is the result of the development of a preliminary software called WD99. This codewas developed in the period 1996-2000 using several platforms. The first release wasdeveloped with the CRAFT programming environment embedded the Cray T3D. Theporting of the code on the Cray T3E system, where the CRAFT was no more available,was performed in 1998 using the shmem library, that was the only one-side communica-tion system available. The performances of the shmem library, in terms of scalability and


latency time are very good, being this library designed for the hardware architecture ofthe Cray T3E and of the Sgi Origin systems. On systems like the IBM SP where theselibraries are not available FLY has been modified to use the local libraries.The MPI-2 library was made available with good declared performances for IBM SP Sys-tem only recently. This library probably will be adopted in the next FLY version (2004),to increase the code portability.In the FLY code, we have implemented a set of cosmological equations of motion, solvingthe standard particle equations of motion for a Friedmann cosmology.

The code is organized in some subroutines that are executed at the start of the job onlyand other subroutines that are executed for each time-step. All the input parameter filescan be created using the on-line assistant that does not need a graphical environment.Moreover if the user have installed the wish Tcl/Tk in the system where he want torun FLY, he can use a graphical interface, where he can set the working directory, theexecutable directory and will create the not existing directories. The figures 1 and 2 showthe main window and the window to set the stat pars file. If this file exists, it is loadedwith the values of the existing file. Other files are created using similar windows.

2.6.3 Scientific Visualization

The AstroMD toolkit (Becciani et al. 2001) is a visualization and analysis software (pub-lic domain), specifically oriented to astrophysical data. It is developed in the frameworkof the project Cosmo.Lab, funded by the European Community, which involves severalEuropean astrophysical institutions and the CINECA. This tool gives a 3D graphic rep-resentation of the data exploiting all the available information and making use of theimmersive visualization techniques. AstroMD uses the most advanced visualization tech-nology, based on the virtual reality, in order to build a leading edge instrument both forscientific research and for cultural dissemination and education.In order to build a widely used product it was chosen to use a low cost software portable ona number of different platforms, the Visualization Toolkit (VTK) by Kitware (Schroederet al. 1999). VTK is an open source, freely available software system for 3D computergraphics, image processing, and visualization. It includes a C++ class library and severalinterpreted interface layers. VTK is available for nearly every Unix-based platform (e.g.Linux or IRIX) and PC’s (Windows 2000 and Windows XP). The design and implemen-tation of the library is based on the object-oriented paradigm. The graphical model inVTK is at a higher level of abstraction than rendering libraries like OpenGL or PEX.This means it is much easier to create useful graphics and visualization applications.

2.6.3.1 Basic Functionalities

AstroMD allows the user to treat both particles (unstructured data) and continuous fieldsdiscretely represented over a computational mesh (structured data). Data must be writ-ten as sequences of 3D coordinates in the case of particles and as sequences of scalar values(fortran or C order) in the case of meshes. The input data Formats presently accepted byAstroMD are the common unformatted C standard, the Raw Format, the TIPSY (Univer-sity of Washington, N-Body Shop, http://www-hpcc.astro.washington.edu/tools/tipsy/ti-psy.html) and the FITS Formats(Flexible Image Transport System, http://heasarc.gsfc.na-


Figure 2.46: Formation of clusters of galaxies in the universe, with overdensity of 200compared to the background density, during the evolution of a sample of 150000 particlesin a cubic box of 50 Mpc.

sa.gov/docs/heasarc/fits.html). Raw files are simply dump of the memory, written in acontinuous sequence of x, y, z coordinates.Data are visualized with respect to a box which describes the computational region. Boxescan be translated, rotated, zoomed in and out with respect to selected positions. Coloursand luminosities can be chosen by the user. Images of different evolutionary stages canbe combined in order to obtain a dynamic view of the behaviour of the system. Theopacity of the particles can be increased, so that low density regions are more easily de-tectable, or decreased, so that the details of the high density regions substructures areshown. Different particles species (e.g. dark matter and baryons) can be visualized at thesame time using different colours. Other particles related to continuous quantities, likedensity fields, can be calculated as typical grid based fields and visualized as isosurfacesor volumes.

Scalars fields can be visualized by isosurfaces or by volume rendering. The value ofthe isosurface can be selected on the user interface (Fig. 2.46). The volume renderingcan be calculated using both the texture mapping and the ray tracing technique (Fig.2.47). Different time frames can be shown in a sequence. When the system evolves, theparticles positions can be interpolated between two time-step.

2.6.3.2 Data Analysis Functionalities

Some built-in-tools, specifically directed to cosmological results of simulation, were imple-mented to allow an efficient manipulation and analysis of the data. At present the mainfollowing functionality are implemented.

• Particles mass density

• Gravitational field calculation

• Fourier decomposition, Power Spectrum and Correlation Function

• Minkowski Functionals


Figure 2.47: Volume Rendering displays visual images directly from volume data, enablingthe viewer to fully reveal the internal structure of 3-D data.

• Friend of Friend Algorithm

2.6.4 Grid Computing

This line of research is finalized to the development of technologies based on the Com-putational Grid, through some main activities. The Grid refers to an infrastructure thatenables the integrated, collaborative use of high-end computers, networks, databases, andscientific instruments owned and managed by multiple organizations.

In this project a relevant effort is made to ease the use of complex simulation codesbased on complementary methods and that of complex computational tools (parallel plat-forms with different architectures, heterogeneous platforms, visualization tools).

The INAF-Catania Astrophysical Observatory has an agreement with the INFN (Na-tional Institute for Nuclear Physics) that allows the Astrophysical Observatory to startall the formal procedures and to acquire the know-how to set up a Data Grid node site inour institute. This node is already running in the INFN grid, and will be a node of thefirst Italian Grid for Astrophysics following the international standards in this field.

The research group is funded by the Italian Ministry of Research in the Cofin03 pro-gram, to participate in the first group of the Italian Grid for Astrophysics. We willdevelop the software for general purposes and concerning cosmological simulations thatcan be executed on the grid, the use of AstroMD as an analysis tool and visualization ofdata distributed on the grid and the use of the AstroComp portal developed to build thegrid. All the developed tools will be made available for the scientific community.

2.6.5 Astrocomp

This project was developed by researchers from the Observatory of Catania, ”La Sapienza”University and from ENEA Casaccia and funded from the CNR (Agenzia 2000 program)with the project ”Computational Grids and Application” coordinated by Prof. A. Murli.The specific plan of the research unit, was a project called Astrocomp (Costa 2003, DiMatteo 2003), for the creation of a portal based on WEB technologies. Astrocomp is for


Figure 2.48: The Astrocomp Portal (http://www.astrocomp.it).

the management and utilization of open-source codes initially related to the simulationof gravitational systems for astrophysical and cosmological studies.

Astrocomp is a project developed by the Astrophysical Observatory of Catania, Uni-versity of Roma La Sapienza and ENEA, and financed by the CNR.

The project goal is to build a web-based user-friendly interface which allows the inter-national community to run some parallel codes on a set of high performance computing(HPC) resources. There’ s no need for specific knowledge about Unix commands and Op-erating Systems. Astrocomp makes some CPU times, on large parallel platform, availableto the referenced user .Astrocomp is a portal which creates a repository of easily usable computational codesand a common database available to the community. The Astrocomp server is based on aPHP-MySQL environment (Choi et al. ). Registered users have a grant for HPC systemsavailable to the portal and can run all the astrophysical codes of the portal. They caneasily prepare jobs and submit them remotely. The portal allows the user to know in realtime the job status and hardware information of an HPC system like CPU usage, memoryand queue status. Astrocomp looks like a sole interface for users wishing to run parallelcodes included in the portal; it hides HPC complexity creating a common user level.In the framework of the Cofin03 program we will use the infrastructure of Grid.it in orderto use the middleware for the usage of the hardware resources.

2.6.6 Future development

The main scientific researches during the years 2004 and 2005 will be addressed to set theItalian Grid for Astrophysics and the applications porting for the use of the grid comput-ing facilities. The Astrophysical Observatory of Catania will continue and expand all theabove mentioned activities also using the new financed project of the MIUR.The Scientific Visualization will be enhanced considering the application for the GridComputing and the integration towards the Virtual Observatory standards, and also con-sidering some aspects related to low cost new technologies for immersive visualization;

THE DIGITATION OF THE ARCHIVE OF ASTRONOMICAL PLATES 75

the FLY project will include new features for the integration of the code with hydrody-namical codes like FLASH, and an interface to run FLY and FLASH in a grid computingenvironment will be designed and developed. Grid-based projects will be also developedjointly with the INFN for the extension of Astrocomp functionalities as a Globus-basedportal. OACt MPP computing systems will be linked to the INFN Grid, that will allowthe OACt to include computing facilities in the INFN Grid.

2.7 The digitation of the archive of astronomical plates

of Catania Astrophysical Observatory

INAF Researchers: E. MarilliUniversity Researchers: C. BlancoTechnical Staff: V. Greco, A. Mangano, P. Massimino

The research is financially supported by MIUR (COFIN 2002).The use of CCD devices to digitize photographic plates, will allow the extraction of

their immense scientific patrimony of information in the various fields of astronomicalsurveys, from the stellar variability, to stellar and galactic dynamics, to the location ofNear-Earth Asteroids. Large quantity of information is contained in photographic archivesof many Italian Observatories with plates that date from the end of XIXth century to theend of the recently passed century. An accurate digitation of such patrimony is thereforeof fundamental importance both for its conservation and for its full scientific use.

The Catania Observatory within the COFIN 2002 project, has put as main objective,the digitalization and informatic archiving of both the plates obtained between 1970 and1985 with the telescope Schmidt 41/61 at the observing station ”M.G. Fracastoro” ofthe Catania Astrophysical Observatory and the plates obtained between 1897 and 1907at Catania as participation to the historical international project of the ”AstrographicCatalogue” and of the ”Carte du Ciel”. Additional plates obtained with the same in-strumental apparatus, from 1956 to 1964, to search for large proper motion stars in thefield of astrographic zone of Catania have been included. In any case only the plates ofthe astrophotographic catalogue in a sufficient state of conservation are considered forthe archiving and the digitalization. A feasibility study for the restoration of those notcompletely damaged has been started.

A detailed inspection of the photographic plate archive of Catania Observatory hasallowed to pick out approximately 2000 plates whose cataloguing is in progress. At thesame time, the digitalization of the plates has begun, with particular care to the criteriaof optimization and homogenization procedures to be used inside the collaboration withthe other Research Units. Among the approximately 1600 plates (format 16x16 cm),obtained from 1897 to 1907 for the Astrographic Catalogue and the Carte du Ciel, about500 plates, little damaged or easily recoverable for the digitalization could have a usefulscientific value, have been selected. Among those, 30 plates of the Halley comet, obtainedin the 1910 from January to June, all in acceptable conditions, have been characterized .Only 2 of these plates had been already reproduced in ”Atlas of Comet Halley 1910 II”(NASA 1986), while the remaining has been brought back now in evidence. All the platesare undergone the digitalization and the images analysis has already begun.

A work station, equipped with high performances EPSON 1680pro scanner, has been


already acquired in analogy with other italian observatory participant to the project. Itis dedicated to the informatic archiving and digitalization of the plates.

In the framework of the activity of the Catania Research Unit, the software ”As-troplates”, which allows to analyse the images of photografic plates acquired with thescanner, has been developed in the graphical environmend IDL (Interactive Data Lan-guage). The program has been written in MS Visual Basic 6,0 and runs in any 32 bitMicrosoft environment. It permits to manage the different operative phases, from thedigitalization to the storing in various formats (TIFF, FITS, JPEG), the header of thefits files, the archiving and the analysis of the images.

The results of the activity of the Catania Research Unit have been presented, togetherwith the activities of the other Research Units taking part to the Project, to the XLVIIAssembly of the SAIt ([110], [72]) to the XXV General Assembly of the InternationalAstronomical Union [144], to XII Joint European National Astronomical Meeting [130]and accepted for the publication in Experimental Astronomy .

Chapter 3

Projects and Collaborations

3.1 National and international projects

The research activity at Catania Astrophysical Observatory is going on in the frameworkof a number of national and international projects and collaborations, the most importantof which are:

REM. REM (Rapid Eye Mount) is a small rapid reaction automatic telescope for near-infrared spectroscopy, devoted to the monitoring of the prompt afterglow of γ-Ray Burst(GRB) events detected by the NASA SWIFT satellite. One of the most important char-acteristics of this instrument is the fast pointing system which will enable the detection ofthe GRBs [Zerbi et al., Astronomische Nachrichten, 2001]. In 2003, during the phase ofcommissioning, Rodono, Cutispoto and Distefano have monitored the young open stellarcluster Trumpler 26 as a part of a long-term program on angular momentum evolution oflate-type stars.

WSO/UV. Activities related to the implementation and phase A study of the WorldSpace Observatory/Ultraviolet (WSO/UV) telescope have been carried out at CataniaObservatory [73], [113], [129].

WSO/UV is a project based on a fully open international collaboration, which ismeant to provide advanced observing capabilities in the ultraviolet (UV) range. TheWSO/UV satellite is planned to be a 1.7 m telescope operative in the classical UV (115nm to 310 nm), equipped with a medium/high-resolution plus a long slit low-resolutionspectropraphs, high-sensitive and high-resolution UV cameras and an optical camera. Itslaunch is planned for 2008, and it will be operated at the Lagrangian point L2 for 5(+5) years. A multinational Phase A study is at moment in progress in several countries(e.g. Russia, Germany, China, UK, Spain, Italy, Israel, etc) where National WSO/UVWorking (NWWG) groups have been formed, under the coordination of the WSO/UVImplementation Committee (WIC). I. Pagano during 2003 has continued to be part of theWIC and to coordinate the Italian NWWG. Specifically, I. Pagano, as primary investigatorof a proposal submitted to ASI for funding the Phase A study of the FGS of WSO/UV– to be performed at industrial level – has participated to the iteration process requiredby the ASI Unit ”Observations of the Universe” and organized in a series of workshops inRome. Moreover, I. Pagano has participated to the WIC meeting held in VILSPA (ESA),Madrid on 10-12 December where a report on the Italian participation has been given aswell a contribution to the science primary objective discussion.

COROT & Eddington. Reasearchers at Catania Observatory have continued the col-

77

78 CHAPTER 3. PROJECTS AND COLLABORATIONS

laboration with other scientists in Europe for the preparation of the COROT and Edding-ton space projects. Both COROT and Eddington are space experiments, coordinated byCNES (France) and ESA respectively, dedicated to ultra high precision, wide field, rela-tive stellar photometry, for very long continuous observing runs on the same field of view.Their scientific programs are : 1) search for extrasolar planets, with Eddington capablealso to detect telluric planets, and 2) asteroseismology [146], [147], [150].

Specifically, G. Cutispoto, I. Pagano and S. Messina [91] have continued to monitora selection of primary targets for the COROT asteroseismology program with the 91cmSLN telescope of the M.G. Fracastoro site, to evaluate the level of magnetic activity inthese stars and their rotation periods by analyzing high resolution spectra (R 20,000) inthe region of Ca II H & K lines. First results from the analysis of these data have beenpresented at the COROT Week No. 5 in Berlin 10-13 Dec 2003.

S. Messina with P. Parihar and B.J. Medhi fron Indian Institute of Astrophysics (IIA)have carried out a spectro-photometric monitoring with the 2-m HCT telescope aimedat characterizing a sample of nearly 200 late-type stars in the COROT’s astroseismologyand exoplanet fields.

A.F. Lanza and I. Pagano, in collaboration with M. Rodono and collaborators atCatania University and at the Laboratoire d’Astronomie Spatiale in Marsiglia (France)continued their studies to address the influence of stellar activity on the detection ofplanetary transits [29], [141], [98]. Results has been discussed during the COROT WeekNo. 4 in Marsiglia, Jun 3-6 2003, and the COROT Week No. 5 in Berlin, 10-13 Dec 2003.

Letters of interest for the Additional Programmes of the COROT mission have beensubmitted by Lanza, Messina and Pagano in response to the Call issued by the COROTScientific Committee on Jul 12 2003. A talk on these interests has been given during theCOROT Week No. 5 in Berlin, 10-13 Dec 2003.

GAIA space mission. A contribution to the GAIA Radial Velocity Spectrometer(RVS) optimization study has been given by Pagano and Busa, Rodono [115; 85]. GAIA(http://astro.estec.esa.nl/GAIA/) has been selected as a forthcoming ESA Cornerstonemission and it is designed to obtain extremely precise astrometry (in the micro-arcsecregime), multi-band photometry and medium/high resolution spectroscopy for a largesample of stars. In particular, GAIA spectroscopy will be obtained over the 8480-8750A wavelength range, centered on the near-IR CaII triplet and the head of the Paschenseries, where also abundant FeI, SiI, MgI, NI and TiI lines cluster. The spectral resolutionis currently foreseen to be around 20,000.

X-SHOOTER. X-SHOOTER is a high-efficiency medium resolution spectrograph whichwill allow simultaneous coverage of the whole spectral range from the UV (300 nm) to thenear IR (1.9 micron). The instrument consists of three separate spectrograph arms forthe UV-Blue, Visual-Red, and near-IR part of the spectrum with a resolution of about10,000. X-SHOOTER will be built by an European consortium comprising ESO, Den-mark, Netherlands and Italy. Within the Work Package on Detector systems, the Cataniagroup, due to its recognized expertise in the area of detectors and associated electronicswill cooperate with ESO in the characterization of the optical detector systems.

SoHO/UVCS and SHARP Spadaro and Ventura continued their involvement in theSoHO/UVCS project as witnessed by the work described in Sect. 2.1. Moreover, Spadarohas been recently appointed Responsible for the scientific coordination of the space ex-periment SPECTRE (i.e., Spectroheliograph for the Transition Region, the P.I. of whichis E. Antonucci from INAF-Turin Observatory) a segment of the Solar and Heliospheric

3.2. COLLABORATIONS 79

Activity Research and Prediction Program (SHARPP) having as P. I. R. Howard fromNaval Research Laboratory - Washington. SHARP is a NASA mission developed in theframework of the program ”Living with a star” and is to be launched in 2007. The ex-periment SPECTRE is a contribution from the Italian solar physics community and itis devoted to the study of the solar transition region, the interface separating the solarchromosphere from the corona from which most of the solar EUV emission is originatedand the site of remarkable dynamic phenomena affecting the outer atmosphere of theSun. In addition to Spadaro, also the other solar physicists of Catania Observatory andUniversity are getting involved in the project.

3.2 Collaborations

In the scientific context of the researches carried out at Catania Observatory severalcollaborations with single scientists and Institutions are going on as listed below:

Solar Physics:

- Dip. Astronomia Univ. Firenze, Firenze: G. Noci

- Dip. Scienze Fisiche e Astronomiche, Univ. di Palermo, Palermo: G. Peres

- Institut d’Astrophysique Spatiale, Parigi (Francia): J.C. Vial, P. Lemaire

- Naval Research Laboratory, Washington (DC, USA): S.K. Antiochos, et al.

- INAF Osservatorio Astronomico di Palermo, Palermo: S. Orlando

- INAF Osservatorio Astronomico di Torino, Pino Torinese (TO): E. Antonucci

Stellar Physics:

- Armagh Observatory, Armagh (North Ireland): C.J. Butler, J.G. Doyle

- Astrophysikalisches Institut Potsdam (Germany): K.G. Strassmeier, G.Rudiger, D.Elstner, Th. Granzer

- Canada-France-Hawaii Telescope Corporation: E. Magnier, E. Menard

- Complejo Astron’omico El Leoncito (Argentina): S. Malaroda

- Catholic University of America (IACS), Washington (DC, USA): R.D. Robinson

- Dept. of Physics and Astron., College of Charleston (NC, USA): J.E. Neff

- Dept. of Physics and Astronomy, Rutgers University, (NJ, USA): M. Gagne

- Dip. Scienze Fisiche e Astronomiche, Univ. di Palermo, Palermo: G. Peres

- Goddard Space Flight Center, Greenbelt (MD, USA): HST/STIS Team

- Ege University Observatory, Bornova, Izmir, Turchia: C. Ibanoglu, S. Evren

- European Southern Observarory, Garching bei Munchen (Germania): L. Pasquini


- European Southern Observarory, Santiago del Cile (Cile): M. Kurster, S. Bagnulo

- Indian Institute of Astrophysics, India: P. Parihar

- Istitute d’Astrophysique de Paris, Paris (Francia): M. K. Andre’

- Inst. d’Astrophys. Spatiale,Paris XI, Orsay (Francia): P. Gouttebroze

- Istit. di Radioastronomia del CNR, Noto (SR): C. Buemi, P. Leto, C. Trigilio, G.Umana

- Institute for Astronomy, University of Hawaii : E.L. Martın

- Joint Institute for Laboratory Astrophysics, Boulder (CO, USA): J.L. Linsky, A.Krishnamurthi

- Johns Hopkins University, Baltimora (MD, USA): L. Bianchi, P. Sonnentrucker

- Laboratoire d’Astrophysique de Marseille (France): P. Barge, M. Deleuil

- Lockheed Palo Alto Research Co., Palo Alto (CA, USA): B.M. Haisch

- NASA InfraRed Telescope Facility, Honolulu (HI, USA): W. Vacca

- National Astronomical Observatory, Sofia (Bulgaria): N. Markova

- National Optical Astronomical Observatory, Tucson (AZ, USA): J. Valenti

- Observatoire de Grenoble: C. Dougados

- Observatoire Midi-Pyrenes (Francia): J. F. Donati

- Obs. Astronomique, Univ. Strasbourg (France): R. Freire-Ferrero, A. Fresnau, J.Guillot

- INAF Osservatorio Astronomico di Brera, Merate (MI): G. Chincarini, G. Taglia-ferri, L. Pastori, E. Antonello, L. Mantegazza, + REM Group

- INAF Osservatorio Astronomico di Capodimonte, Napoli: E. Covino, J Alcala, R.Silvotti

- INAF Osservatorio Astronomico di Palermo, Palermo: R. Pallavicini, A. Maggio

- INAF Osservatorio Astronomico di Roma: F. D’Antona, C. Maceroni

- INAF Osservatorio Astronomico di Torino: M. Villata, C. M. Raiteri

- Observatoire de Paris: A. Baglin, et al.

- South African Astronomical Observatory, Cape Town (Sud Africa): P. Martinez

- Space Telescope Science Institute, Baltimora (MD, USA): N. Panagia

- Special Astrophysical Observatory of the Russian (Russia): D.N. Monin

3.2. COLLABORATIONS 81

- Theoretical Astrophysics Center, Aarhus (Danimarca): J. Christiansen-Dalsgaard,F. Pijpers, H. Kjeldsen

- Univ. Federale del Rio Grande du Norte, Natal (RN, Brasile): R. de Medeiros

- University of Chicago, Chicago (IL, USA): R. Rosner

- University of Southampton (UK): P. Maxted

- University of Sussex, Department of Physical Sciences (UK): R.P. Fender, S.K.Yerli

- University of Villanova, Villanova (PA, USA): E.F. Guinan

- University of Western Ontario (Canada): J. D. Landstreet

- University of Cape Town, Cape Town (Sud Africa): D. Kurtz

- University of Toronto, Toronto (Canada): G. Wade

- University of Wien, Vienna (Austria): M. Stift

Experimental Astrophysics and Solar System:

- German Aerospace Center, DLR, Berlin: Ljuba Moroz

- INAF Osservatorio Astronomico di Roma: Elisabetta Dotto

- INAF Osservatorio Astronomico di Capodimonte, Napoli: J. Brucato, V. Mennella

- INAF Osservatorio Astronomico di Cagliari, Cagliari: G. Mulas

- NASA-AMES Laboratory (CA, USA): Y. Pendleton

- University of Catania, Department of Chemistry: G. Compagnini.

- University of Charlottesville, VA: R. Baragiola, B. Johnson

- University of Lecce, Department of Physics: V. Orofino, A. Blanco

- University of Valencia, Spain: M. Satorre, O. Gomis, M. Domingo

Galaxies and Cosmology:

- Inst. of Astron., Univ. of Edinburgh (UK): E. van Kampen

- Lebedev Instit. for Theoretical Physics, Mosca (Russia): V. Lukash et al.

- Universita di Copenhagen (TAC), Copenhagen (Danimarca): J. Sommer Larsen

- Universita dell’ Insubria, Como: A. Treves

- Universita ”La Sapienza”, Roma: E. Massaro, R. Nesci

- INAF Osservatorio Astronomico di Torino, M. Villata

Image Detectors and image Processing:


- CARSO (Center for Advanced Research in Space Optics), Trieste: R. Stalio

- Dipartimento di Fisica, Universit di Firenze, Firenze: P. Spillantini

- English Electric Valve, Chelmsford (UK): P. Jorden

- European Southern Observarory, Garching bei Munchen (Germania): J. Beletic

- Istituto di Fisica Cosmica del CNR, MIlano: M. Uslenghi

- INAF Osservatorio Astrofisico di Arcetri, Arcetri (FI): E. Pace

- INAF Osservatorio Astronomico di Brera, Merate (MI): R. Citterio

- INAF Osservatorio Astronomico di Padova, Padova: R. Gratton, F. Bortoletto

- INAF Osservatorio Astronomico di Palermo, Palermo: R. Pallavicini

Others:

- CINECA, Casalecchio di Reno (Bo): G. Erbacci e R. Ansaloni (Calcolo ad AltePrestazioni), C. Gheller e L. Calori (Visualizzazione Scientifica)

- Ottica Marcon, S. Dona di Piave (VE): progetto APT/2-80cm

Chapter 4

Facilities and Services

4.1 Buildings

The restoration of the main building of the Osservatorio Astrofisico was completed by theend of the year. It was financed by the Universita degli Studi di Catania, which is theowner of the building, and by the Observatory. The plan and the direction of the workswere under the responsibility of the deputed Office of the University Technical SupportService. The Technical Support Office of the Observatory has been deeply involved duringall the phases of the works to warrant a proper consideration of all the specific require-ments for the disactivation and re-activation of the installations and plants as well as formoving around the offices and various facilities from the working areas.

The new high-vacuum facility building for mirror allumination at the mountain stationM. G. Fracastoro have been granted by the deputed public authorities of all requiredpermissions. The prime contractor for the construction have been selected after a publicannouncement issued at the beginning of 2003. Works will start on April 2004

The plan for the re-structuring of the building housing the automated telescopes at theM. G. Fracastoro station was approved by the deputed public authorities (genio Civile andthe Comune di Ragalna) and by the Parco dell’Etna who recommended the implementa-tion of a scheme consisting of three folding domes in order to minimize the environmentalimpact. The selection of the prime contractor for the construction was accomplishedby the Ufficio di Catania del Genio Civile a Competenza Statale as deputy office of theObservatory. Works are expected to start on April 2004

The roof of the main building at the M. G. Fracastoro mountain station damaged bythe snow and ice during winter 2001-2002 has been completely restored.

The specific plan of the extra-ordinary maintenance work has been prepared by theGenio civile office in Catania, who has also the responsibility of work realization.

4.2 Acquisition of new instrumentation and facilities

The enhancement and the renewal of the scientific facilities have gone on in 2003 accordingto the annual programme. Moreover, using the saving on expenses obtained in the budgetof previous years, it has been possible to get new instrumentation and facilities. The mostimportant ones acquired in the course of 2003 are:

• A linear turning-lathe made by Mexim was installed in the mechanical workshop;

83

84 CHAPTER 4. FACILITIES AND SERVICES

• A new CCD detector for the Raman spectrograph;

• The quenching controller for the SPAD detector;

• The new generation controller for the CCD camera of the APT80/2 was deliverd bySkythec;

• The IBM SP4 P650 - 8 processors 16 GB RAM for the HPC project.

4.3 Library

Scientific supervisor: R. VenturaStaff: A. Mangano, M. Calı, G. Caripoli, D. Domina,

D. Recupero, G. Santagati.

The library collection of Catania Astrophysical Observatory presently includes 10303volumes, 126 journal titles, 234 antique (see Fig. 4.1 and 4.2) volumes and a number ofaudio-video materials. The library content is mainly specialized in Astronomy and Astro-physics, but two significant sections are also devoted to General Physics and Mathematics.Moreover, a special section, dedicated to education is continuously updated with cd-romsand video-tapes.

The library is open to astronomers, technicians and staff of the Observatory and toteachers belonging to the Departments of the Catania University as well as to researchersand University students of several institutions and faculties, and to all interested visitors(by permission).

Opening hours: from Monday to Saturday, from 8:15 to 13:45 and on Monday, Wednes-day and Thursday from 14:30 to 17:30. Services: Loan; interlibrary-loan; document de-livery service.

Due to the restoration work inside the Observatory building, the reading room was notavailable during all the year and some reading space was provided inside the main libraryhall. The routine maintenance activities were reduced to essential and urgent tasks inconsideration of the limited space available.

• Acquisitions and inventory (G. Caripoli, D. Domina, M. Calı)

Due to the decrease in the Observatory budget for goods and services, funds avalaiblefor the library in 2003 amount only to 40.000 euros, which were spent to buy booksand for journal subscriptions. The reduction in the funds implied a remarkabledecrease in the number of renewed subscriptions for the year 2004. The selectionof the renewed subscriptions was made by taking into account the indication ofthe research and technical staff as well as the availability of the journals throughother observatories or institutes belonging to the national library network ArchivioCollettivo Nazionale Periodici (ANCP). The on-line services provided by the CentroBiblioteche e Documentazione of the University of Catania granted access to severalon-line journals and further helped to reduce the cost of subscriptions. In general,the reduction in costs for every single acquisition was also made possible by thecomparison of on-line offers and by the services offered by the libraries consortium

4.3. LIBRARY 85

Figure 4.1: Library historical section, Agelli (1718): Galileo Galilei portrait, taken from“Opere di Galileo Galilei nobile fiorentino Accademico Linceo” by Franciscus Agelli,Firenze, 1718.

(ESO, CNR-Bologna, CILEA; CBD- Catania, INAF) which provided free journalsin a mutual exchange regime.

• Cataloging (D. Domina, A. Mangano)

New books acquired in 2003 (about 115) have been cataloged according to descrip-tive and semantic rules, with the UNIBIBLIO software. The relative bibliographiccontrol has been made when the records have been exported to build the web cat-alogue. The semantic cataloging has been made using an Italian Subject Index(edited in 1999) which refers to that of the Library of Congress and to the IAUThesaurus. The new software MILLENNIUM – a new integrated web-based cata-loging software provided by the University of Catania – has been tested and usedfor some limited applications.

• Journals catalogue (L. Santagati, A. Mangano)

The update of the journals list has been performed following the on-line procedure ofthe Archivio Collettivo Nazionale Periodici (ACNP), adopted by the library. Thus,the ACNP catalogue now includes a number of 410 journals.

In 2003 the on-line service of document delivery has increased (about 110 both bythe Italian Observatories and other Institutes participating to the ACNP consortiumand other inter-library exchange organizations seeking for specific articles).

• Historical Archive and Catalogue (A. Mangano)

In the framework of the national project Specola 2000 which gathers all the ItalianObservatories with the aim of developing and making the historical collections ac-cessible, the Soprintendenza Archivistica per la Sicilia committed the inventory of


Figure 4.2: Library historical section, Newton (1760): left panel) cover from “Isaaci New-ton optices libri tres: accedunt ejusdem lectiones opticae, et opuscula omnia ad lucem& colores pertinentia”, Isaac Newton, Patavii (Padova), 1749; right panel) cover from“Philosophiae Naturalis Principia Mathematica”, Isaaco Newtono, Sumptibus Cl. & Ant.Philibert Bibliop., 1760.

the historical archive to an external collaborator. The bibliographic part and thecorrespondence was previously sorted by the librarians.

The joint work of the collaborator and of the Observatory staff librarians led during2002 to the completion of the inventory of the historical archive for the period1865-1954. It is presently accessible in printed form and contains seven series ofdocuments of great importance for the history of Catania Observatory. The seriesof letters has already been requested for consultation by various users, both internaland external.

• Scientific secretariat and Preprints (D. Recupero, L. Santagati)

Twenty-six preprints have been printed and distributed to 47 Italian and foreignAstronomical Institutes and Observatories. All the preprints were made accessiblealso through the web site of the Observatory.

Several papers have been linguistically reviewed.

The organization of the Workshop “Modeling the Intergalacting and InterstellarMedia” held in Vulcano (Me), Italy from October 1 to 4, 2003 and the Workshop“Adaptive Techniques in Computational Astrophysics and Biology” held in Cataniafrom November 12 to 14, 2003 were managed.

• Loan, reference service, electronic information service (D. Domina, A. Mangano,D. Recupero, L. Santagati, G. Caripoli)

The reference service for students and researchers consists in the search in the local

4.4. COMPUTING CENTER AND LOCAL NETWORK 87

catalogues, both printed and on-line, and other external catalogues using internetfacilities. The intense collaboration between the libraries of the other Italian Ob-servatories has enhanced thanks to the CUBAI (Catalogo Unico Biblioteche Astro-nomiche Italiane) and ACNP Astronomical projects. Other collaborative links havebeen established (CIBD Centro di Coordinamento delle Biblioteche dell’Universitadi Catania and other foreign institutions) in the framework of a more and moreintense inter-library cooperation.

An automatic procedure had been fixed to daily update the record of the IAU(since 1999) and the MPEC Circulars (from 2001), both available full text throughelectronic subscription.

• Public outreach and education (D. Domina, A. Mangano)

The end of 2003 marks the establishment of the POE, with the aim of enhancingthe activity of public outreach and education organized by the OAC. The libraryis responsible for the public relations with schools and people interested in visitingthe Catania Observatory and the mountain station M. G. Fracastoro or asking forinformation about the history of the Observatory or general astronomy.

• Activity in coordination with INAF

During the year 2003, frequent exchanges were held among the librarians of theItalian observatories, coordinated within INAF. The library staff of Catania Ob-servatory contributed to several significant aspects, assisted also by an expert incomputer science for the development and implementation of new software for anew national astronomical library service. The development of a National Librarysystem for INAF has been proposed in order to optimize the available resourcesand made them fully available to the research community. A detailed report on thelibrary of Catania Observatory was prepared as a first step for contributing to thisproject according to the guidelines specified the deputed INAF working group.

4.4 Computing Center and local network

Supervisor: P. MassiminoStaff: A. Costa, C. Lo Presti, A. Giuffrida

Catania site: The computing center consists of central machines and distributed work-stations, running various operating systems:

• Central machines (computing servers):

– SUN Sparc 20 (UNIX) Server and Sun cluster

– Compaq DS10 (Open VMS)

– SG Origin 200 with two processors (UNIX)

– LINUX Cluster based on 7 PCs AMD 1.4 GHz

– IBM 9076-550 SP3 with 24 parallel processors and the new IBM SP4 P650 8processors 16GB


• Network server:

– PC Linux Suse 7.2 (astrct: DNS, SSH ..., FTP, WEB and the solar imagearchives)

– PC MS-WindowsNT (netserver, interactive Web services for astronomy andlibrary)

– a LAN consisting of 75 personal computers and workstations for the researchstaff, technicians and administration staff.

– four laser printers

During 2003 the implementation and reconfiguration of the components which mustguarantee the security of information systems have been continued. New facilities havebeen implemented. The problem of security has been among the main issues of this year.

The principal specific activities can be summarized as follows:

• The wireless connection between Catania the M. G. Fracastoro station at SerraLa Nave has been completed both on the hardware and software implementation.Software parameters have been settled to extend the Observatory LAN to Serra LaNave. On the same time the firewall Sonicwall Pro 200, supplied with the ”HighAvailability” software, was reconfigured to protect access to SLN LAN through theWAN.

• The astrct server, on which the SMTP, DNS, FTP, IMAP, POP, SSH, are activehas been implemented on a new more performant PC, based on a faster CPU with1 GB RAM.

• The computing resources available on the Linux cluster (NIS server) were updatedand upgraded by including new nodes. Also the software configuration has beenchanged, moving from LINUX Mandrake to SUSE 8.2 operating system. A largemass memory his available on the NIS server as back-up utility for data of personalworkstations. One node is exclusively dedicated to mass memory sharing and tomanagement of the printer queues.

• The configuration of a new cluster of the Beowulf type, based on a 4 LINUX SUSE8.2 nodes and on PVM and MPI software libraries has been settled.

• The configuration of the grid computing INAF-CT, node of the GRID.IT networkhas been completed. It Include 5 operating units: the Server dedicated to the nodeinstallation, the Computing Element dedicated to the managements of computingresources, the Storage Element providing the mass memory management, the UserInterface for the management of user certification and the Worker Node which makeavailable the computing power.

• Within the works of the building restoration the LAN cabling system was reorga-nized. A backbone made by three main lines was set to feed three concentratorscomposed by Switches of 10/100 Mbit/sec. More than 140 access point to the LANwere distributed over all offices and labs.

• New utilities for the network monitoring (snort, Razor etc.) have been activated tocollect useful statistics for the optimization of the system.

4.5. OPTO-MECHANICAL WORKSHOP AND TELESCOPES AUTOMATION 89

• The anti-spamming control system available on the SMTP server is continuouslyupdated with new versions of the two main components, MailScanner and SpaAs-sassin, which seek for viruses on e-mail and spamming messages.

OA Catania Web siteThe observatory web page is continuously updated. The new implemented resources in-cludes: information on Public Out-reach and Education and a service for the staff Avvisial Personale, the access to which is restricted to internal users connecting through theObservatory’s LAN. The on-line catalogue of the Observatory’s library has been contin-uously updated and made available to internal and external internet users to the MPECand IAU circulars. Moreover, the electronic versions of our preprints were made fully ac-cessible through internet in collaboration with the library and scientific secretariat staff.The new server www.astrocomp.it was furtherly improved with the installation of LINUXGentoo and the serverCUPS.

Training activities and participation to scientific meetingsP. Massimino and A. Costa attended the V Garr workshop. Some different meeting ofthe system managers of Italian Observatories of INAF were attended by P. Massimino onbehalf of Catania Observatory. P. Massimino and A. Costa are involved in the projectDataGrid, as a collaboration with INFN. P. Massimino is still continuing its collaborationin the project for the scanning and digitization of old photographic plates belonging tothe collection of Catania Observatory.

4.5 Opto-mechanical workshop and telescopes automa-

tion

INAF staff: G. Carbonaro, G. Gentile, M.P. Puleo, E. Martinetti,M. Miraglia, S. Sardone, P. Bruno

The practical activity of opto-mechanical workshop in 2003 was actually very reducedbecause all machines were dismounted due to the building restoration works. Most of thetime was dedicated to new projects reconsideration and design.

4.5.1 Telescope automation

91-cm Cassegrain telescope: The new software ”Asterix 2000”, installed and commissionedin 2001 confirmed its stability and operation effectiveness. The software converting thetelescope coordinates into the azimuthal system has been made ready to interface theelectronic encoder system providing the position of the dome, making a further step tothe complete automation of the telescope. The tracking software developed within theLab-view environment, updated with a 10 bit A/D converter board has been furtherlyimproved developing new utilities: evaluation of the instantaneous seeing on the image ofthe tracking star memorization of the reference point coordinate of the tracking positionof the field of view, i.e. the center of the optical fiber for the spectra acquisition. Thecurrent accuracy of the tracking is about 0.5 arcsec with corrections typically applied ontimescales of 5 s. The accuracy in the tracking may be improved by using more frames,but a limit is set by the telescope mounting mechanics.


On the base of the optical imagine quality at the Cassegrain focus tested by means ofa Schack-Hartmann wavefront analyzer, a new moveable mechanical supports of the sec-ondary mirror has been designed. The new support will allow X-Y shift of the secondarymirror to correct mis-allignement due to the flexures of the tube At different inclinationof the telescope. The best seeing measured at the M. G. Fracastoro station was of theorder of 1 arcsec, hence the improvement of the telescope optical quality according to theabove plan is highly recommendable also in consideration of the foreseen application ofa photometric CCD camera and of the use of an optical fiber of 100 micron core for thespectrograph.

61-cm Schmidt telescope: The project of the mechanical revision has been critically re-examined and updated before starting the operative phase. In particular, a series of testsshowed that it is not possible to use a system based on a double pinion and a brakefor moving the telescope in declination without angular clearance. Moreover, the doublepinion system with an electric pre-loading would require a cooling system of the enginestoo complicated for application to a 61-cm telescope. Therefore, the whole system wasre-designed considering the user of a brushless torque engine manufactured by ETELwhich does not need braking and cooling systems and is capable of operate under a loadunbalance up to 100 kg. The design phase was completed and the engine and the encoderhave been commissioned. The controller is similar to that of the Galil system and isthus fully compatible with the control software Asterix, the standard operation softwaremanaging all our telescopes. The engine was delivered by the end of the year. Drawingsof the mechanical interface are now completed, and the construction of mechanical partshas already started .

APT-80/1: A fault occurred in the telescope controller cannot be repaired because thenecessary electronic components are out-of-stock. The whole acquisition and control sys-tems has been re-designed, to enable the telescope operation under a more flexible newcontrol hardware and software. The new system is based on brushless engines under con-trol of a GALIL processor, the same as on the other telescopes, thus approaching a uniformcontrol system for all telescopes. The software for the telescope pointing and tracking isloaded as GALIL firmware, thus making the control software on the PC dedicated totelescope handling and to data acquisition more flexible. Actually the communicationsystems between the two units has revealed more complex than expected, causing somedelay in the project. However some test of pointing and measurement acquisition havebeen already done.

APT-80/2: The mechanics and the mirrors of the telescope have been completed bythe Marcon firm. The pointing and tracking operations have been successfully testedat Marcon Lab implementing the Asterix 2000 software, thus confirming its reliabilityand portability. Pointing and repeatability accuracy, tested with a laser beam, matchesthe constraints requested to the manufacturer. The requirements of the domes, whoseaperture must be compatible with the automatic movement of the telescopes have beenfurtherly analyzed. In addition to the retractable enclosure made by folding material pro-posed by the Halfmann Teleskopetechnik GmbH, a metallic version is being considered inorder to increase stiffness against wind and snow load.

4.6. CCD IMAGE ACQUISITION 91

4.5.2 Opto-mechanical laboratory

Spectro-polarimetric module: The spectro-polarimetric module for the REOSC echellespectrograph mounted at the 91-cm telescope is currently used, and the positioning andalignment set-up of the polarizing elements has been improved .

New off-set guider: The new offset guiding system for the 91 cm telescope has been com-pleted. Tests on the mirror probe positioning, based on a programmable high-precisioncontroller (10 microns in the positioning accuracy) have confirmed the project specifica-tions. The system will be definitely installed as soon as the CCD camera will be ready

Focal reducer and CCD camera: A focal reducer for the CCD camera was built withtwo filter wheels for UBVRI filters. The filter wheel control software is under test asseparate task, and it is ready to be included in the image acquisition system software.The CCD camera, with a newly conceived Peltier cooling system, is under construction bythe firm Hitech under the supervision of the detector research group of the Observatory.The camera uses a 1024x1024 CCD with 24 micron pixels; it will have a 10 arcmin fieldof view and is expected to reach a magnitude 18 with S/N=100 in 10 min.

Spectrograph fiber link: A new fiber link to feed the spectrograph using a 100 micronfiber with glued micro-lens on the input side has been implemented. The new systemprepared as test for the new spectrograph has produced a significant improvement in thelink efficiency and allowed a better resolution (R= 22.000) due to the smaller size of thefiber. The micro-lent set-up was kindly made by Gerardo Avila ate ESO. The mechanicalcoupling of the fiber to telescope focal plane has been improved making the connectionmore reliable.Technical installations: The opening and closing system of the solar telescope dome inCatania has been provided with a wire free power supply and tele-command. It is basedon autonomous batteries fed by two solar cell, thus allowing to open or close the dome inany dome position without the repositioning near the plug-in power supply location. Asimilar is in progress to be installed on the dome of 91 cm telescope.

4.6 CCD image acquisition

Supervisor: G. BonannoINAF Researchers: R. Cosentino, S. ScuderiTechnical staff: M. Belluso, P. Bruno, A. Calı, M.C. Timpanaro

The activity of the image acquisition system done by the detector group, as far as themaintenance and implementation of new cameras and control systems carried out in 2003is as follow:

Solar CCD Camera: The old CCD camera bought more ten years ago has undergoneaccurate maintainance both on the electronics and the cooling system. A Ciller


devices for the pre-cooling and temperature stabilization of the Peltier cell has beenadopted.

Imaging CCD camera for the 61-cm telescope: The new camera, cooled by Peltier ef-fect cell, designed and manufactured by the group has been tested at the AsiagoSchmidth telescope. The test give very good results on the image quality and controlsoftware, but the the mechanical system of movements for changing filters neededsome revision.

Imaging CCD camera for the 91-cm telescope: The camera for the 91-cm telescopecoupled to the focal reducer has been subject of some design revision. A thinshutter has been incorporated on the front face of the camera. This camera will becooled by a three stages Peltier effect cell able to reach temperatures of −60 C.The final design has been committed to Hitech a technical firm in Catania underthe supervision of the group. Tests on the vacuum and the limiting temperature arein progress.

4.7 Photometric data acquisition and reduction

Supervisor: E. MarilliTechnical Staff: V. Greco, C. Lo Presti, P. Massimino

The photometric laboratory activity on 2003 has been mainly dedicated to the hard-ware and software maintenance as follows:

• The setup and testing of the single channel photometer for the acquisition of pho-tometric data at the focal plane of the 91-cm telescope at Serra La Nave.

• Upgrade of the software for acquisition, reduction and storage of data implementedon the last version of OBELIX written in Visual Basic (Win Obelix).Operation mode have been described in previous reports.

The group has also supporting and updating the software ”PHOT” for the data re-duction, which allows the rapid data reduction for differential magnitudes, standard UBVand Stromgren system. The package which runs in DOS and VMS environment is char-acterized by a high degree of flexibility.

4.8 The ”Mario G. Fracastoro” station on Mt. Etna

Supervisor: A. FrascaTechnical staff: G. Carbonaro, A. Di Stefano, A. Micciche, M. Miraglia,

G. Occhipinti, M. G. PuleoMaintenance staff: R. Caruso, G. Corsaro, C. Scuderi

The observing station of Catania Astrophysical Observatory is located at Serra La Nave(SLN), on Mt. Etna, at an altitude of about 1700 m a.s.l. It has been dedicated to Profes-sor Mario G. Fracastoro, who promoted its building during the period of his directorship(1954-1967). This site is about 40 km far from Catania and 20 Km from Nicolosi, thenearest village. Four telescopes are installed in three different domes:

4.8. THE ”MARIO G. FRACASTORO” STATION ON MT. ETNA 93

• The 91-cm Cassegrain reflector [Fig. 4.3]

• The 61/41-cm Schmidt-Cassegrain Universal Telescope

• The automatic Ritchey-Chretien photometric telescope (APT/1-80cm)

• A 30-cm Cassegrain reflector, hosted in the APT/1-80cm’s building.

The 30-cm telescope is used for educational purposes and outreach activities, e.g., studenttraining and visitors’ visual observations. Two additional buildings are used as guardianand guest house, respectively. Moreover, the latter building hosts the mechanical andelectronic laboratories for instrumentation maintenance.

The 91-cm Cassegrain reflector mechanical part was manufactured by Marchiori andthe optics by Tinsley. It has been operating since 1965. The optics have a classic design.They allow the use of the telescope at its prime focus and at the newtonian focus, with arelative aperture f/4.68, or in a Cassegrain configuration having a f/15 relative aperture.The pointing and tracking system, originally operated by the observer and equipped withfixed frequency engines, has been replaced with brushless engines and digitized readingof coordinates. A Pentium PC with Asterix 2000 – a software specifically developed byour technical staff – drives the telescope in semi-automatic mode.

Figure 4.3: The 91-cm Cassegrain reflector with fibre feed interface

The 91-cm telescope is usually used with the Cassegrain configuration, with the fol-lowing instruments:

• REOSC Echelle spectrograph (f/15 collimator and CANON camera f=300 mm,f/2.8) with the possibility of observing in single dispersion (resolution of 0.9 A/pxl)


or cross dispersion (resolution of 0.15 /pxl). The spectrograph is connected to thetelescope by means of an optical fibre and during 2000 it has been equipped witha polarimetric module for the measurement of the linear and circular polarization,allowing the determination of the four Stokes parameters. The acquisition systemconsists of a CCD camera (1024x1024, with 24 micron pixels), managed by the samesoftware developed for the TNG cameras.

• Single head photometer for UBV photometry, ubvy-Hγ and cometary bands (IHW).The photometer can perform photometry with maximum time resolution of 0.1 and0.5 s, using a single filter or different filters sequentially inserted, respectively.

• Double-channel photometer URSULA for simultaneous UBV photometry of twonear objects (decommisioned).

• Near IR photometer (JHKLM bands) with InSb sensor, cooled by liquid nitrogen,which is normally used up to K band (2.2 micron) (decommisioned).

• CCD Camera. Some tests have been carried out with the controller developed forthe TNG telescope and a focal reducer with a field of view of about 10′ is underconstruction as above explained.

The 61/41 cm Universal Schmidt-Cassegrain telescope, built by ”Meccanica Sartidi Bologna” (1966) is completely manually operated. The Schmidt configuration has arelative aperture of f/3.5 and a field of view of 4.2 × 4.2 degrees in the photographicmode. It is equipped with a secondary mirror which allows a quasi-Cassegrain focus, witha nearly null field of view, used only for photoelectric photometry. The photometer con-tains standard UBV filters mounted on a rapidly rotating wheel (0.1 Hz), which performsquasi-simultaneous measurements in the three filters (maximum time resolution of 1 sec)and is particularly suitable for the study of rapidly evolving events, such as stellar flares.The telescope is presently being restored in order to implement an automatic control ofthe pointing and tracking system, also for objects with large proper motion. It will beequipped with a CCD camera for the monitoring of Near Earth Orbit (NEO) asteroids inthe framework of the ITANET project.

The APT/1-80cm (Automated Photoelectric Telescope) built by AutoScope Co.(Tucson AZ, USA) was installed at the end of 1991. The optical configuration is a Ritchey-Chretien type with absolute aperture of 80 cm and equivalent focal of about 6 m. Boththe telescope and the photometer (UBV) are automatically operated by a PC-AT/386.The observational efficiency (duty-cycle), over a 10-year operation period, has been es-timated to be of about 70%, while the traditional telescopes seldom get 30-40%. Thesystem is completely automated, including the opening and closing of the sliding roofs ofthe rectangular block (4× 8 m) hosting it. The opening command of the roof is activatedafter a meteorological test is passed, on the basis of fixed meteorological limits (absenceof rain, fog, strong wind and so on).

The telescopes of the M.G. Fracastoro stellar station operate for about 350 nights ina year. Six technicians in turn guarantee the night technical assistance. The 91-cm and

4.8. THE ”MARIO G. FRACASTORO” STATION ON MT. ETNA 95

Cassegrain 91-cm APT/1 80-cm2000 2001 2002 2003 1999 2000 2001 2002

Nightly use > 50% 156 156 161 164 157 183 100 89Nightly use < 50% 34 38 29 23 70 38 41 18

Maintenance and testing 35a 26 31 0 10 6 15 3Not used (meteo) 115 135b 138 62 117 124 196b 199c

Not used (failure) 26 10 6 72d 11 15 13 66Notes: (a) Including the period of inactivity (60 days) spent for the aluminizationof the mirrors and the revision of the bearing of the primary mirror(b) Including the time spent for the aluminization of the primary mirror (20 g days)(c) Including 30 nights of inactivity due to the eruption of Mt. Etna(d) Including 59 nights of inactivity due to money lack

Table 4.1: Telescopes activities

the APT/1-80 cm are fully time allocated, while the 61-cm Schmidt telescope is presentlyunder revision.

The statistics relative to the use of the telescopes nights/year are listed in Table 4.8:

Research programs: During 2003 the following research programs have been carriedout at the M. G. Fracastoro station:

• Systematic long-term study of stellar activity by means of wide-band photometry(APT 80)

• Structure of the chromosphere and its evolution for variable stars belonging to theRS CVn and T Tauri groups by means of spectroscopic monitoring of the Hα line;

• Correlation between photospheric spots and chromospheric faculae in RS CVn bi-naries by simultaneous optical photometry and spectroscopy

• Measurement of the temperature variation associated with stellar spots

• Characterization of the promary targer of the space mission COROT

• Rotation of young stellar objects (PMS and T Tauri)

• Measurements of chemical abundances and magnetic fields in CP and Ap stars

• Partecipation to coordinated multi-site campaign for the observation of Blazars andToO

• Mass loss determination in variable stars of the P Cygni class

• Spectroscopic studies of planetary nebulae

• Pulsations of sdB stars.


Figure 4.4: Distribution of publications totally or partially based on observations madeat the M. G. Fracastoro station

The papers published in internationally referred journal and the invited contributiontotally or partially based on observations made at the M. G. Fracastoro station (see alsoFig. 4.4) are: [5], [7], [9], [10], [12], [14], [15], [19], [25], [27], [35], [38], [50], [51], [54], [57],[91], [95], [94], [105], [107], [124], [134], [146], [152]

4.9 Solar observation facilities

Supervisors: D. Spadaro, F. ZuccarelloTechnical staff: E. Catinoto, P. Costa (since June 2003) and S. Sciuto

Equatorial spar. The equatorial spar (see Fig. 4.5) consists of 6 optical benches, threeof which are devoted to the daily observing program:

• a bench for the white light observations, sunspot shape and sunspot group drawing;

• a bench for Hα observations, chromosphere and photosphere with Zeiss filter (CCDcamera); the detector was replaced by a new E2V 1360x1200 CCD array

• a bench for Hα visual observations, Halle filter.

The data acquired in the framework of this program deal with: groups of sunspots,faculae, quiescent and active prominences on the disk and at the limb, flares (see Fig. 4.6).

The standard sequence of observations consists of:

4.9. SOLAR OBSERVATION FACILITIES 97

Figure 4.5: The equatorial spar.

• one image every 15 min at the center of the Hα line (chromosphere);

• one image every 15 min in the Hα line wing (+5A, photosphere);

• rapid sequences of images during flares or eruptive prominences.

Catania Observatory makes available solar observations also through its web site.It shows links to several international research projects and collaborations to which itactively contributes.

Since 2002, Catania Astrophysical Observatory is one of the stations of the GlobalHigh-Resolution Hα Network, which collects and records chromospheric data obtained byseveral international observatories. This network, which includes also the facilities of theBig Bear Solar Observatory (California, USA), the Kanzelhohe Solar Observatory (KSO)in Austria, the Huairou Solar Observing Station (HSOS) and the Yunnan AstronomicalObservatory (YNAO) in China, allows to monitor continuously activity phenomena oc-curring in the solar chromosphere, enabling to follow with high accuracy the evolutionof active regions and to enhance our knowledge of such phenomena. The aim is to usestatistically analysis to solve the question related to the flares prediction.

Solar observations carried out in Catania also support the activities of the French-Italian solar telescope THEMIS (Tenerife, Canary Islands). Hα full disc images hourlycollected are put on the web page of Catania Observatory, in order to help in the selectionof solar regions to observe by THEMIS (whose instantaneous field of view is smaller than1 arcmin × 1 arcmin), also taking into account the longitude difference between CanaryIslands and Catania.


Figure 4.6: An Hα a image of the Sun taken with the Zeiss filter.

Chapter 5

Out-reach and Education

Education and public conferences are part of the institutional activities of the CataniaAstrophysical Observatory as science education is a key factor for social development.The impact of the out-reach programs carried out at Catania Observatory on people, andespecially on the youngest, living in the Catania area and in general in eastern Sicily, hasbeen improved every year by means of an intense and increasing activity.

Conferences and visits to the Observatory site in Catania (at the “Cittadella Univer-sitaria”) are typical winter time activity. Most of the visits requests come from Sicilianschools but in many cases schools and various organizations from outside Sicily are hosted.After a general or specific argument presentation, in case of precise request, the visit to thesolar facilities and the direct observation of the Sun is allowed. During the more favorablespring and summer seasons visits are organized also to the “M. G. Fracastoro” observa-tory mountain station. In that case the visit includes a tour to one of the telescopes andobservations of the moon and some of the visible planets, galaxies and nebulae.

5.1 Out-reach Office

Supervisors: G. Cutispoto, G. LetoSupport Staff: D. Domina, A. Mangano, G. Occhipinti

During 2003 the out-reach activity have been largely incremented (see Fig. 5.1), as-tronomers of OACt have given their support to the out-reach activity together with as-tronomers of the Department of Physics and Astronomy of the Catania University, PhDstudents and post-doc fellows. Many programs where coordinated with various organiza-tions. As usual we contributed to national and international events like the “Sun-Earthdays” and the “ IV Settimana della Cultura Scientifica e Tecnologica” organized by Min-istero dell’Istruzione, dell’Universita e della Ricerca (MIUR).

A special effort has also been done to get funding for this service to the community. Thenecessary development of instruments like a dedicated telescope for visual observationsand multimedia projections systems have been partially supported by MIUR/SSPAR.

In the following sections we give the complete list of all the conferences and visits heldduring this year.

99

100 CHAPTER 5. OUT-REACH AND EDUCATION

5.1.1 Public conferences

During 2003 a number of Conferences and courses where solicited to the Out-reach office.

• 17 Gennaio - ”Il Sistema Solare” - Cir. Did. ”Maria Teresa di Calcutta” (plessoSettebello), Tremestieri Etneo (CT) - I. Pagano

• 24 Gennaio - ”Il Sistema Solare” - Cir. Did. ”Maria Teresa di Calcutta” (plessoImmacolata), Tremestieri Etneo (CT) - M.E. Palumbo

• 10 Febbraio - ”Le nuove frontiere dell’Astronomia” - Liceo Scientifico Statale ”Archimede”(”Osservatorio ”Archimede”), Acireale (CT) - S. Catalano

• 11 Febbraio - ”I pianeti intorno al Sole e alle altre stelle” - UNITRE, sede di Catania- A. Lanza

• 13 Febbraio - ”Il Sistema Solare” - Cir. Did. ”Maria Teresa di Calcutta” (plessoCentro), Tremestieri Etneo (CT) - M.E. Palumbo

• 18 Febbraio - ”L’evoluzione delle stelle e l’origine della vita” - UNITRE, sede diCatania - A. Lanza

• 19 Febbraio - ”Le dimensioni dell’Universo” - Liceo Scientifico Statale ”Archimede”,Acireale (CT) - S. Scuderi

• 20 Febbraio - ”Telescopi dell’era moderna” - Associazione Astrofili Ionico-Etnei,Riposto (CT) - G. Catanzaro

• 28 Febbraio - ”Il Sistema Solare e le stelle” - Istituto Statale Comprensivo ”G.Verga”, Centuripe (EN) - A. Lanza

• 18 Marzo - ”Noi e il Sole: vivere con una stella” - conferenza pubblica - Dipartimentodi Fisica e Astronomia, Universit di Catania - D. Spadaro

• 19 Marzo - ”Il Sistema Solare” - Circolo Didattico ”Licatia” - Catania - G. Leto

• 26 Marzo - ”La scomparsa dei Dinosauri: Collisione della Terra con grandi Asteroidi”- UNITRE, sede di Vittoria & International INNER WHEEL - Vittoria (RG) - G.Cutispoto

• 7 Aprile - ”Oltre le leggi di Keplero” - Assiciazione Nazionale Insegnanti di ScienzeNaturali - Catania - M. Ternullo

• 8 Aprile - ”Formazione degli spettri stellari” - 1o Istituto di Istruzione Superiore -Pachino (SR) - G. Catanzaro

• 6 Maggio - ”Le origini dell’Universo” - DIESSE & Giovent Studentesca - c/o Liceo”Maria Adelaide” - Palermo - A. Lanza

• 22 Maggio - ”Origine della vita ed Evoluzione Stellare” - Associazione Insegnanti diFisica c/o convitto ”M. Cutelli” - Catania - A. Lanza

5.1. OUT-REACH OFFICE 101

• 17 Luglio - ”Le Stelle e i Pianeti” - Cooperativa Sociale D.O.C. - Soggiorno A.R.C.A.(CT) - G. Cutispoto

• 19 Luglio - ”L’inquinamento Luminoso del Cielo” - Convegno regionale Archeoam-biente su ”Inquinamento luminoso tra cielo e Terra” - Riposto (CT) - G. Catanzaro

• 5 Agosto - ”L’Universo in laboratorio” - Liceo Scientifico Statale ”Archimede” (”Os-servatorio ”Archimede”), Acireale (CT) - G. Strazzulla

• 6 Agosto - ”Oltre le leggi di Keplero” - conferenza pubblica - ”Natura e Scienza aRagalna 2003” - Comune di Ragalna (CT) & CEDRA - M. Ternullo

• 30 Agosto - ”Marte 2003: mai cosı vicino” - conferenza pubblica - Istituto TecnicoNautico - Riposto (CT) - G. Catanzaro

• 3 Settembre - ”Il pianeta Marte e la sua esplorazione” - Liceo Scientifico Statale”Archimede” (”Osservatorio Archimede”), Acireale (CT) - G. Leto

• 2 Ottobre - ”La ricerca dei pianeti extrasolari” - Liceo Scientifico Statale ”Archimede”(”Osservatorio Archimede”), Acireale (CT) - F. Catalano

• 1 Dicembre - ”La riscoperta del Sistema Solare” - Liceo Scientifico Statale ”Archimede”(”Osservatorio Archimede”), Acireale (CT) - C. Blanco

• 16 Dicembre - ”I corpi minori del Sistema Solare” - Associazione Astrofili Ionico-Etnei, Riposto (CT) - G. Catanzaro

5.1.2 Visits to the Observatory

As every year many schools and various organization asked for conferences and a guidedvisits to both the “Cittadella Universitaria” site and to the “M. G. Fracastoro” mountainstation. In both cases the visits are split in two parts, the first one is dedicated to a generalintroduction to Astronomy and Astrophysics, the second part is a visit to the telescopewhere people have the opportunity to perform observations at the telescope and ask morequestions to the astronomer. In the case of visit to the “Cittadella Universitaria” site theequatorial spar is used to make live observations of the sun and its active reagions, whilein the case of visits to the “M. G. Fracastoro” mountain station usually observations ofthe Moon and planets are done by using the facilities available at the 91 cm telescope. Insummer 2003, as usual, the Observatory has organized the telescopes opening to public.The events have been advertised by local newspapers as “Osservatorio Astrofisico: visitepubbliche”. The goal of these events is to give singles, families or group of people thepossibility to spent few ours visiting the telescopes site on mount Etna.

Here is the list of the visits, the name of the leading astronomer is included.

Visits to the Observatory main building at the “Cittadella Universitaria”:

• 20 Settembre - Lions Club - Niscemi (CL) - D. Spadaro

• 06 Novembre - Liceo Scientifico ”Leonardo” - Giarre (CT) - L. Contarino

• 11 Novembre - Liceo Scientifico ”leonardo” - Giarre (CT) - P. Romano


• 13 Novembre - S.M.S. ”Raffaello Sanzio” - Tremestieri Etneo (CT) - G. Catanzaro

• 15 Novembre - Liceo Scientifico ”M. Cipolla” - Castelvetrano (TP) - G. Cutispoto

• 18 Novembre - Liceo Scientifico ”Leonardo” - Giarre (CT) - A. Bonanno

• 20 Novembre - S.M.S. ”Raffaello Sanzio” - Tremestieri Etneo (CT) - M.E. Palumbo

• 25 Novembre - Ist. Comprensivo N.1 - Capo D’orlando (ME) - A. Lanza

• 27 Novembre - Liceo Scientifico ”Principe Umberto” - Catania - S. Messina

• 29 Novembre - I.T.C.S. ”E. De Nicola” - S.G. La Punta (CT) - I. Pagano

• 02 Dicembre - Istituto ”Maria Ausiliatrice” - Caltagirone (CT) - A. Lanza

• 04 Dicembre - Liceo Scientifico ”Principe Umberto” - Catania - D. Spadaro

• 06 Dicembre - Circ. Didat. ”A. Diaz” - Catania - V. Antonuccio

• 09 Dicembre - S.M.S. ”G. Verga” - Acicastello (CT) - M.E. Palumbo

• 16 Dicembre - Ist. Compr. ”V. Brancati” - Pachino (RG) - P. Romano

• 18 Dicembre - Liceo Ginnasio ”M. Morelli” - Vibo Valentia - S. Messina

• 20 Dicembre - Liceo Scientifico ”G.B. Odierna” - Palma di Montechiaro (RC) - I.Pagano

Visits to the Observatory telescopes at the “M. G. Fracastoro” mountainstation, Etna (Ragalna, Ct):

• 28 Marzo - Ist. Comprensivo ”E. Fermi” - Catenanuova (EN) - S. Messina

• 28 Marzo - Liceo Scientifico ”G. Berto” - Vibo Valentia - S. Messina

• 11 Aprile - Circolo Did. ”Madre Teresa di Calcutta” - Belpasso (CT) - G. Cutispoto

• 11 Aprile - S.M.S. ”G. Garibaldi” - Realmonte (AG) - G. Leto

• 11 Aprile - Liceo Ginnasio ”N. Spedalieri” - Catania - G. Leto

• 13 Aprile - ”Open Day” - I. Pagano, G. Leto, G. Cutispoto

• 23 Aprile - III Circolo Did. ”V.F. Crispi” - Gravina di Catania (CT) - A. Lanza

• 23 Aprile - Liceo Scientifico ”G. Galilei” - Catania - A. Lanza

• 24 Aprile - Circolo Did. ”Madre Teresa di Calcutta” - Belpasso (CT) - G. Cutispoto

• 24 Aprile - Istituto Tecnico Commerciale Statale ”Filadelfo Insolera” - Siracusa -G. Cutispoto

• 24 Aprile - Liceo Ginnasio Statale ”Gorgia” - Lentini (SR) - E. Marilli


• 28 Aprile - Liceo Ginnasio Statale ”Gorgia” - Francofonte (CT) - G. Catanzaro

• 29 Aprile - Ist. Prof. di Stato ”Mauro Perrone” - Castellaneta (TA) - G. Leto

• 29 Aprile - Lic. Gin. Stat. ”A. Cascino” - Piazza Armerina (EN) - G. Catanzaro

• 30 Aprile - Liceo Scientifico ”Elio Vittorini” - Lentini (SR) - G. Cutispoto

• 30 Aprile - Liceo Scientifico ”V. Romano” - Piazza Armerina (EN) - G. Cutispoto

• 2 Maggio - I Istituto di Istruzione Superiore - Pachino (SR) - G. Catanzaro

• 5 Maggio - Ist. Stat. ”E. Pantano - A. Olivetti” - Riposto (CT) - G. Cutispoto

• 5 Maggio - XIII Ist. Comprensivo ”Archimede” - Siracusa - G. Cutispoto

• 5 Maggio - Ist. Com. ”F. Costa” - S. Michele di Ganzaria (CT) - G. Cutispoto

• 5 Maggio - Liceo Scientifico ”E. Medi” - Barcellona P.G. (ME) - G. Cutispoto

• 6 Maggio - Liceo Paritario ”M. Ausiliatrice” - Catania - E. Marilli

• 8 Maggio - Liceo Scientifico ”Maiorana” - S.Giovanni la Punta (CT) - G. Cutispoto

• 9 Maggio - S.M.S. ”Nosengo” - Gravina di Catania (CT) - S. Messina

• 9 Maggio - Liceo Classico ”Eschilo” - Gela (AG) - S. Messina

• 10 Maggio - Circolo Didattico ”L. Capuana” - Piazza Armerina (EN) - I. Pagano

• 10 Maggio - San Paolo IMI, Succursale di Catania - I. Pagano

• 19 Maggio - Liceo Scientifico ”G. Galilei” - Modica (RG) - G. Cutispoto

• 20 Maggio - S.M.S. ”L. Sturzo” - Biancavilla (CT) - A. Lanza

• 21 Maggio - Liceo Scientifico - Canicattini B. (SR) - G. Catanzaro

• 21 Maggio - Ist. Tec. Comm. ”De Felice Giuffrida” - Catania - G. Catanzaro

• 22 Maggio - I.T.I.S. ”Cannizzaro” - Catania - G. Leto

• 22 Maggio - Liceo Ginnasio ”Sacro Cuore di Ges” - Catania - G. Leto

• 22 Maggio - Liceo della Comunicazione ”N. Spedalieri” - Bronte (CT) - A. Frasca

• 23 Maggio - I.P.S. per l’Industria e l’Artigianato - Acri (CS) - S. Messina

• 23 Maggio - S.M.S. ”S. Todaro” - Augusta (SR) - S. Messina

• 23 Maggio - Ist. Statale Istr. Secondaria Superiore ”F. Fedele” - Agira (EN) - S.Messina

• 5 Giugno - Comunit Terapeutica Riabilitativa ”J.F. Kennedy” - Adrano (CT) - G.Catanzaro


• 6 Giugno - 2E Circolo didattico ”E. De Amicis” - Catania - I. Pagano

• 6 Giugno - Visita pubblica - G. Leto

• 7 Giugno - 3A e 3B Centro Scolastico ”Licatia”- Catania - I. Pagano

• 7 Giugno - Visita Pubblica - G. Leto

• 8 Giugno - Visita Pubblica - G. Cutispoto

• 4 Luglio - Visita Pubblica - G. Cutispoto

• 6 Luglio - Visita Pubblica - G. Catanzaro


• 21 Luglio - C.A.I. sede di Belpasso (CT) - G. Cutispoto

• 22 Luglio - 850 Club Italia - Aci S. Antonio (CT) - G. Cutispoto

• 23 Luglio - Gruppo Azione Cattolica parrocchia ”S.S. Trinita e S. Marziano” -Lentini (CT) - G. Cutispoto


• 3 Agosto - Visita Pubblica - S. Messina

• 4 Agosto - Visita Pubblica - F.A. Catalano

• 5 Agosto - Visita Pubblica - S. Messina

• 6 Agosto - Centro Culturale ”Solidariet” - Centuripe (EN) - A. Lanza



• 9 Agosto - ITT-NAS Base NATO Sigonella (CT) - I. Pagano

• 10 Agosto - AGESCI (Associazione Guide e Scout Cattolici Italiana), Gruppo Sir-acusa 9 - A. Bonanno

• 12 Agosto - Serata speciale per l’osservazione delle ”Perseidi” - I. Pagano, G. Leto

• 13 Agosto -Serata speciale per l’osservazione delle ”Perseidi” - I. Pagano, G. Leto

• 22 Agosto - Visita Pubblica - G. Catanzaro

• 27 Agosto - Serata speciale per l’osservazione di Marte - I. Pagano, G. Leto

• 29 Agosto - Visita Pubblica - G. Leto

• 1 Settembre - Visita Pubblica - G. Cutispoto

• 2 Settembre - Visita Pubblica - G. Catanzaro



• 4 Settembre - Visita Pubblica - G. Leto

• 5 Settembre - Visita Pubblica - S. Messina




• 11 Settembre - Rotary International, Distretto 2110 Sicilia-Malta - E. Marilli

• 12 Settembre - Istituto scolastico ”Babilonia” - Taormina (ME) - G. Leto

• 15 Setembre - Visita Pubblica - G. Catanzaro


• 20 Settembre - Lions Club - Niscemi (CL) - G. Leto


• 23 Settembre - Questura di Catania - M.P. Di Mauro

• 24 Settembre - Visita Pubblica - G. Catanzaro


• 26 Settembre - Marina Militare - Augusta (SR) - G. Catanzaro

• 1 Ottobre - Visita Pubblica - G. Cutispoto

• 2 Ottobre - Visita Pubblica - A. Lanza

• 3 Ottobre - Visita Pubblica - A. Frasca

• 3 Ottobre - Genio Civile di Catania - S. Catalano

• 4 Ottobre - Liceo Scientifico ”G. Galilei” - Modica (RG) - I. Pagano (con la collab-orazione di G. Occhipinti)

• 6 Ottobre - Ist. Mag. Stat. ”Regina Elena” - Acireale (CT) - G. Catanzaro

• 7 Ottobre - S.M.S. ”N. Martoglio” - Belpasso (CT) - G. Cutispoto

• 8 Ottobre - Lic. Scient. Stat. ”E. Boggio Lera” - Catania & ”Sint-Jozef” Instituut- Bruxelles - G. Catanzaro

• 29 Ottobre - I.T.I. ”De Felice Giuffrida” - Catania - G. Catanzaro

• 31 Ottobre - Liceo Scientifico ”Leonardo da Vinci” - Niscemi (CL) - G. Leto

• 23 Novembre - ”Gruppo Astrofili Catanesi” - G. Leto

• 6 Dicembre - Club Alpino Italiano (Sezione di Napoli) - G. Catanzaro


Figure 5.1: Number of people visiting our observatory from 1994 to 2003

5.1.3 Special events

During 2003, two special events have been organized, in order to give people the uniqueopportunity to learn more about popular topics as meteor showers and the opposition ofthe planet Mars.

On August 12th - 13th, 2003, the mountain station M. G. Fracastoro was availablefor the public. The oraganized visits included an outdoor conference with a multimediapresentation and direct observation of the meteor shower. More than 300 people weresplit in groups guided by I. Pagano and G. Leto.

A similar event was organized for the opposition of Mars on August 27th, 2003. Morethan 350 partecipants attended to the conference “Agosto 2003: la grande opposizione diMarte” and afterwards observed the red planet with one od the telescopes of the M. G.Fracastoro station. People have been guided to their visit by I. Pagano and G. Leto.

5.2 University Courses and high level Educational

Activity

During 2003 a number of courses and lectures have been given by OACt researchers:

• Lecture on “The Universe extension” (19th Feb) given by S. Scuderi to a class ofthe ”Liceo Scientifico Archimede” in Acireale (CT)

• Training course for students of the ”Istituto Tecnico Archimede” in Catania. In theframe of this course the students have to develop small projects according to theirpersonal school formation using the facilities of COLD laboratory of the CataniaObservatory.

• “CCD detectors characterization”, Physics course of the Department of Physics andAstronomy, Catania University, S. Scuderi

• “Vibrational Spectroscopy as method of analysis of solids in laboratory and in astro-physical enviroments”, Physics course of the Department of Physics and Astronomy,Catania University, G. Strazzulla and G. Leto

5.3. PH.D. STUDENTS 107

5.3 Ph.D. Students

Ph.D. students preparing thesis work with tutorship of Catania Astrophysical Observatoryresearcher during 2003 were:

- Biazzo Katia: “Precise photospheric temperature measurements from line-depthratios”

- Ferro Daniela: “Modelli N-Body e tools di visualizzazione e di analisi“

- Leccia Silvio: “Asteroseismology of solar-type stars: results from high-resolutionspectroscopy”

- Romeo Alessio: “The Evolution of the X-ray luminosoty funcion of galaxy Clusters”

Chapter 6

Staff members

During 2003 a few personnel positions at the INAF-OAC have got some changes. Asan exception to the employement stop, as disposed by the 2002 financial law, Dr. M.Messineo, who was the winner for the competition of a D1 position in 2002, has beenallowed to hold the position. The turn-over from a D3 to a C1 position categories, afterpermission by INAF central office, allowed the employement of Mr. G. Busne with a C1position. Mr. M. Puleo retired starting from July 1st.

After permission in derogation, Dr. A.F. Lanza, Dr. A. Magazzu and Dr. D. Spadaro,who passed the respective competition, have been employed as Associate Astronomersfrom May 6.

6.1 Staff on 31 December 2003

ASTRONOMI

OrdinariBonanno G., Catalano S., Strazzulla G.

AssociatiBaratta G., Cutispoto G., Lanza A. F., Marilli E., Spadaro D., Magazzu A. (On leave

at Telescopio Nazionale Galileo)

RicercatoriAntonuccio V., Becciani U., Bonanno A., Busa I., Catanzaro G., Cosentino R., Di Mauro

M. G., Frasca A., Lanzafame G., Leone F., Leto G., Messina S., Pagano I., Palumbo M.E.,Scuderi S., Ternullo M., Ventura R.

AREA AMMINISTRATIVO-CONTABILE

Categoria EP3Del Popolo S., Rapisarda M.L.

Categoria D1

109

110 CHAPTER 6. STAFF MEMBERS

Messineo M.

Categoria C5Mellini M., Tringale G.

Categoria C2Scafili M.

Categoria C1Busne G., Romania V.

AREA DELLE BIBLIOTECHE

Categoria D3Mangano A.

Categoria C3Domina D., Recupero D., Santagati L.

AREA TECNICA ed ELABORAZIONE DATI

Categoria EP3Massimino P. (ind elab dati)

Categoria EP2Sardone S. (ind. ottico-meccanico), Spinella F. (ind. elettronico)

Categoria EP1Presti C. (ind. elab. dati)

Categoria D3Caripoli G., Catinoto E., Di Benedetto R., Sciuto S.

Categoria D1Belluso M., Costa A.

Categoria C5Bruno P. (elab. dati), Greco V., Martinetti E.

Categoria C3Calı A., Carbonaro G., Gentile G., Lampo R., Miraglia M., Wanausek A.

Categoria C2

6.1. STAFF ON 31 DECEMBER 2003 111

Bellassai M. (uff. tecnico)

Categoria C1Costa P., Occhipinti G., Micciche A.

AREA DEI SERVIZI GENERALI, AUSILIARI E TECNICI

Categoria B4Puleo M. G., (ind. mecc.)

Categoria B3Calı M., Castorina G., Distefano A. (ind. mecc.), Giuffrida A. (ind. elab. dati), Sac-

cone R. (ind. amm.), Timpanaro M.C. (ind. elettronico)

Categoria B2Corsaro G., Santocono O., Scuderi C., Ventimiglia A., Zingale G.

Categoria B1Caruso M. R.

112 CHAPTER 6. STAFF MEMBERS

List of Publications

7.1 Refereed papers

[1] Alonso M. S., Lopez-Garcia Z., Malaroda S., Leone F.: Elemental abundance studiesof CP stars. The helium-weak stars HD19400, HD34797, HD35456, Astronomy &Astrophysics 402, p. 331-334, 2003

[2] Antonuccio V., Becciani U.,Ferro D.: FLY. A parallel tree N-body code for cosmo-logical simulations. Reference Guide, Computer Physics Communications 155, p. 159,2003

[3] Baratta G. A., Domingo M., Ferini G., Leto G., Palumbo M. E., Satorre M. A.,Strazzulla G.: Ion irradiation of CH4-containing icy mixtures, Nuclear Instrumen-tation and Methods B 209, p. 283-287, 2003

[4] Brucato J. R. , Strazzulla G., Baratta G. A., Mennella V., Colangeli L.:LaboratoryStudies on Silicates Relevant for the Physics of TNOs, Earth Moon Planets, 92, 307-313, 2003, c2004

[5] Bonanno A., Catalano S., Frasca A., Mignemi G., Paterno L.:PG 1613+426: anew sdB pulsator, Astronomy & Astrophysics 398, p. 283-285, 2003

[6] Bonanno A., Esposito G., Rubano C.:A Class of Renormalization Group InvariantScalar Field Cosmologies, General Relativity and Gravitation 35, Issue 11, p. 1899-1907, 2003

[7] Bonanno A., Frasca A., Lanza A. F., Ventura R., Mignemi G., Silvotti R.: As-teroseismology of Pulsating sdB Stars Observed at Catania Astrophysical Observatory,Baltic Astronomy 12, p. 287-294, 2003

[8] Bonanno A., Rezzolla L., Urpin V.: Mean-field dynamo action in protoneutron stars,Astronomy & Astrophysics 410, p. L33-L36, 2003

[9] Bottcher M., Marscher A. P., Ravasio M. ,Villata M., Raiteri C. M., Aller H. D. ,Aller M. F., Terasranta H., Mang O., Tagliaferri G. and Frasca A., Marilli E.,Catalano S.: Coordinated Multiwavelength Observations of BL Lacertae in 2000,The Astrophysical Journal 596, p. 847-859, 2003

[10] Cakirli O., Ibanoglu C., Frasca A., Catalano S.: H-alpha variations of the RSCVn type binary ER Vulpeculae, Astronomy & Astrophysics 400, p. 257-264, 2003

113

114 LIST OF PUBLICATIONS

[11] Cataldo F., Baratta G. A., Ferini G., Strazzulla G.: He+ ion bombardment ofC70 fullerene: an FT-IR and Raman study, Fullerene Nanotubes and Carbon Nanos-tructures 11, p. 191-199, 2003.

[12] Catanzaro G., Andre M. K., Leone F., Sonnentrucker P.: High resolution spec-troscopy of HD 207538 from Far-UV (FUSE) to Visible (SARG-TNG), Astronomy &Astrophysics 404, p. 677-687, 2003

[13] Catanzaro G., Bianchi L., Scuderi S., Manchado A.: Spectroscopy of early-typestar candidates in M33 and NGC6822. II, Astronomy & Astrophysics 403, p. 111-117,2003

[14] Catanzaro G., Leone F.: Variability of the HeI5876 A line in early type Chemicallypeculiar stars. Paper II, Astronomische Nachrichten 324-5, p. 445-453, 2003

[15] Catanzaro G., Leone F., Leto P.: HD 191110 a SB2 system with HgMn and Hgcomponents: Orbital elements and abundance analysis, Astronomy & Astrophysics407, p.669-677, 2003

[16] Chincarini G., Cutispoto G., Messina S., Rodono M. et al.: The last born at LaSilla: REM, The Rapid Eye Mount, The Messenger 113, p. 40-44, 2003

[17] Contarino L., Romano P., Zuccarello F., Yurchyshyn V. B.: THEMIS, BBSO, MDIand TRACE observations of a filament eruption, Solar Physics 216, p. 173-188, 2003

[18] Covino S., Malesani D., Tavecchio F., Antonelli L. A., Arkharov A., Di Paola A.,Fugazza D., Ghisellini G., Larionov V., Lazzati D., Mannucci F., Masetti N., BarrenaR., Benetti S., Castro-Tirado A. J., Di Serego Alighieri S., Fiore F., Frontera F.,Fruchter A., Ghinassi F., Gladders M., Hall P. B., Israel G. L., Klose S., MagazzuA., Palazzi E., Pedani M., Pian E., Romano P., Stefanon M., Stella L. : Optical andNIR observations of the afterglow of GRB 020813, Astronomy & Astrophysics 404, p.L5-L9, 2003

[19] Cutispoto G., Messina S., Rodono M.: Long-term monitoring of active stars. X.Photometry collected in 1994, Astronomy & Astrophysics 400, p. 659-670, 2003

[20] Cutispoto G., Tagliaferri G., de Medeiros J. R., Pastori L., Pasquini L., AndersenJ.: Fast-rotating nearby solar-type stars II. Li abundances, v sin i and X-ray lumi-nosities relationships, Astronomy & Astrophysics 397, p. 987-995, 2003

[21] Desidera S., Gratton R. G., Endl M., Barbieri M., Claudi R. U., Cosentino R.,Lucatello S., Marzari F. , Scuderi S.: A search for planets in the metal-enrichedbinary HD 219542, Astronomy & Astrophysics 405, p. 207- , 2003

[22] De Sio A., Donato M. G., Faggio G., Marinelli M., Messina G., Milani E., Pace E.,Paoletti A., Pini A., Santangelo S., Scuderi S., Tucciarone A., Verona-Rinati G.:Spectral response of large area CVD diamond photoconductors for space applicationsin the vacuum UV, Diamond and Related Materials 12, p. 1819, 2003

[23] Di Mauro M. P., Christensen-Dalsgaard J., Kjeldsen H., Bedding T., Paterno L.:Convective overshooting in the evolution and seismology of η Bootis, Astronomy &Astrophysics 404, p. 341-353, 2003

7.1. REFEREED PAPERS 115

[24] Di Mauro M. P., Christensen-Dalsgaard J., Paterno L.: A study of the solar-likeproperties of β-Hydri, Astrophysics and Space Science 284, Issue 1, p. 229-232, 2003

[25] Frasca A., Alcala M., Covino E., Catalano S., Marilli E., Paladino R.: Furtheridentification of ROSAT all-sky survey sources in Orion, Astronomy & Astrophysics405, p. 149-163, 2003

[26] Garcıa-Alvarez D., Foing B. H., Montes D., Oliveira J. M, Messina S., Doyle J. G.,Lanza A. F., Rodono M., Abbott J. B, Ash T. D. C., Baldry I. K., Bedding T. R.,Buckley D. A. H., Cami J., Cao H., Catala C., Cheng K. P., Domiciano de Souza JrA., Donati J.-F., Hubert A. M., Janot-Pacheco E., Hao J. X. , Kaper L., Kaufer A. ,Leister N. V, Neff J. E,. Neiner C., Orlando S., O’Toole S. J., Schefer D., Smartt S.J., Stahl O., Telting J., Tubbesing S.: Simultaneous optical and X-ray observations offlares and rotational modulations on the RS CVn binary HR 1099 (V711 Tau) fromthe MUSICOS 1998 campaign, Astronomy & Astrophysics 397, p. 285-303, 2003

[27] Garcıa-Alvarez D., Barnes J. R., Collier Cameron A., Doyle J. G., Messina S.,Lanza A. F., Rodono M.: Doppler images of the RS CVn binary HR 1099 (V711Tau) from the MUSICOS 1998 campaign, Astronomy & Astrophysics 402, p. 1073-1083, 2003

[28] Katsova M. M., Livshits M. A., Belvedere G.: Butterfly diagrams of strongly spottedlate type stars, Solar Physics 216, p. 353, 2003

[29] Lanza A. F., Rodono M., Pagano I., Barge P., Llebaria A.: Modelling the rota-tional modulation of the Sun as a star, Astronomy & Astrophysics 403, p. 1135-1149,2003

[30] Lanzafame G.: Spirals and shock fronts developed around accretion discs in lineclose binaries: physically viscous and non viscous SPH modelling , Astronomy & As-trophysics 403, p. 593-604, 2003

[31] Leone F., Kurtz D. W.:Discovery of magnetic field variations with the 12. 1-minutepulsation period of the roAp star gamma Equulei, Astronomy & Astrophysics 407, p.L67-L71 , 2003

[32] Leone F., Plachinda S. I., Umana G., Trigilio C., Skulsky M.: The magnetic field ofthe boldmath beta Lyrae system: Orbital and longer time-scale variability, Astronomy& Astrophysics 405, p. 223-226, 2003

[33] Leone F., Vacca W. D., Stift M. J.: Measuring stellar magnetic fields from highresolution spectroscopy of near-infrared lines, Astronomy & Astrophysics 409, p. 1055-1064, 2003

[34] Leto G., Baratta G. A.: Ly-alpha photon induced amorphization of Ic water iceat 16 Kelvin. Effects and quantitative comparison with ion irradiation, Astronomy &Astrophysics 397, p. 7-13, 2003

[35] Massaro E., Giommi P., Perri M., Tagliaferri G., Nesci R., Tosti G., Ciprini S.,Maesano M., Montagni F., Ravasio M., Ghisellini G., Frasca A., Marilli E., Valentini


G., Kurtanidze O. M., Nikolashvili M.: Optical and X-ray observations of the two BLLac objects OJ 287 and MS 1458+22, Astronomy & Astrophysics 399, p. 33-38, 2003

[36] Mennella V., Baratta G. A., Esposito A., Ferini G., Pendleton Y. J.: The Effectsof Ion Irradiation on the Evolution of the Carrier of the 3. 4 Micron InterstellarAbsorption Band, The Astrophysical Journal 587, p. 727-738, 2003

[37] Messina S., Guinan E. F.: Magnetic Activity of six young solar analogues II. Surfacedifferential rotation from long-term photometry, Astronomy & Astrophysics 409, p.1017-1030, 2003

[38] Messina S., Pizzolato N., Guinan E. F., Rodono M.: Dependence of coronal X-RayEmission on Spot-induced brightness variations in cool main sequence stars, Astron-omy & Astrophysics 410, p. 671-684, 2003

[39] Moroz L. V., Baratta G. A., Distefano E., Strazzulla G., Starukhina G. A., DottoE., Barucci M. A.: Ion Irradiation of asphaltite: Optical Effects and Implications forTrans-neptunian objects and Centaurs, Earth Moon Planets, 92, 279-289, 2003, c2004

[40] Palumbo M. E., Strazzulla G.: Nitrogen condensation on water ice, CanadianJournal of Physics 81, p. 217-224, 2003

[41] Romano P. , Contarino L., Zuccarello F.:Eruption of a helically twisted prominence,Solar Physics 214, p. 313-323, 2003

[42] Romano P. , Contarino L. , Zuccarello F. :Magnetic helicity trasport in corona andfilament eruptions, Solar Physics 218, p. 137-150, 2003

[43] Spadaro D., Lanza A. F., Lanzafame A. C., Karpen J. T., Antiochos S. K., Klim-chuk J. A., MacNeice P. J.: A transient heating model for coronal structure and dy-namics, The Astrophysical Journal 582, p. 486-494, 2003

[44] Stift M. J., Leone F.: Magnetic intensification of spectral lines, Astronomy & As-trophysics 398, p. 411-421, 2003

[45] Strazzulla G., Cooper J. F., Christian E. R., Johnson R. E.: Ion irradiation ofTNOs: from the fluxes measured in space to the laboratory experiments Comptes Ren-dus Physique, Academie des Sciences, Paris 4, p. 791-801, 2003

[46] Strazzulla G., Leto G., Gomis O., Satorre M. A.: Implantation of carbon andnitrogen ions in water ice, Icarus 164, p. 163-169, 2003

[47] Zuccarello F., Contarino L., Romano P., Priest E. R.: Flare activity in solar activeregion 8421 observed by TRACE satellite, Astronomy & Astrophysics 402, p. 1085-1102, 2003

[48] Zuccarello F., Zappala R. A.: Angular velocity during the cycle deduced using thesunspot group age selection methodology, Astronomische Nachrichten 324, No. 5, p.464-473, 2003

7.2. EDITED VOLUMES (PROCEEDINGS) 117

7.1.1 Refereed papers in press

[49] Baratta G. A., Strazzulla G., Compagnini G., Longo P.: Raman and photolu-minescence study of ion beam irradiated porous silicon: a case for the extended redemission, Appl. Surface Sci., in press

[50] Blanco C., Cigna M., Riccioli D.: Photoelectric observations of asteroids: rotationalperiod, lightcurves, shape and spin axis determination, Annales de Physique, in press

[51] Blanco C., Cigna M., Riccioli D.: Rotational periods of asteroids. III, Planetary andSpace Science, in press

[52] Brucato J. R., Strazzulla G., Baratta G. A., Colangeli L.: Forsterite amorphi-sation by ion irradiation: monitoring by infrared spectroscopy, Astronomy & Astro-physics, in press

[53] Cataldo F., Baratta G. A., Ferini G., Strazzulla G.: On the effects of He+ ionsbombardment of polyphenilacetylene, Radiation Physics and Chemistry, in press

[54] Catanzaro G., Leto P.: Orbital solution for SB2 systems with HgMn component,Astronomy & Astrophysics, in press

[55] Di Mauro M. P., Christensen-Dalsgaard J., Paterno L., D’antona F.: Interpretationof the solar-like behaviour of eta Bootis, Solar Physics, in press

[56] Ferini G., Baratta G. A., Palumbo M. E.:A Raman study of ion irradiated icymixtures, Astronomy & Astrophysics , in press

[57] Freire Ferrero R., Frasca A., Marilli E., Catalano S.: Magnetic activity in HD111456, a young F5-6 main-sequence star, Astronomy & Astrophysics, in press

[58] Gomis O., Satorre M. A., Strazzulla G., Leto G.: Hydrogen Peroxide Formation byIon Implantation in Water Ice and its Relevance to the Galilean Satellites, PlanetarySpace Science, in press

[59] Pagano I., Linsky J. L., Valenti J., Duncan D. K.: HST/STIS High ResolutionEchelle Spectra of alpha Centauri A (G2 V), Astronomy & Astrophysics, 415, 331

[60] Palumbo M. E. , Ferini G., Baratta G. A.: Infrared and Raman spectroscopyof refractory residues left over after ion irradiation of nitrogen bearing icy mixturesAdvances in Space Research, in press

7.2 Edited volumes (proceedings)

[61] Zuccarello F., Spadaro D., Ventura R.: 3rd National Meeting on the Italian SolarResearch, Memorie Societa Astronomica Italiana, Vol.74, n. 3, 2003


7.3 Invited talks and reviews

[62] Di Mauro M. P.: Heliosismology: a fantastic tool to probe the interior of the Sun,The Sun’s Surface and Subsurface. Investigating Shape and Irradiance, ed. by J. P.Rozelot, Lecture Notes in Physics 599, p. 31-67, 2003

[63] Di Mauro M. P., Paterno L.:Oscillations of the Sun: insights and challenges forthe future, “3rd meeting on the Solar Research in Italy”, Vulcano, Sept. 30 - Oct. 4, 2002, ed. by F. Zuccarello, D. Spadaro, R. Ventura, Memorie Societa AstronomicaItaliana 74, p. 564-571, 2003

[64] Paterno L., Di Mauro M. P., Ventura R.: From helio- to astero-seismology, anew challenge for understanding stellar evolution, Recent Research Developments inAstronomy & Astrophysics, Research SignPost Publ. 1: 523-560, 2003

[65] Spadaro D.: L’irraggiamento solare e le variazioni del clima terrestre,EcoOne conference on ”I cambiamenti climatici” (Castelgandolfo, 2003),http://www.ecoone.org/articoli/pdf/Spadaro Sole Clima.pdf

[66] Spadaro D.: Structure and Dynamics of Magnetic Loops in the Solar Corona, XLVIIS.A.It. Meeting (Trieste, 2003), Memorie Societa Astronomica Italiana Suppl., Vol.3,30, 2003

7.3.1 Invited talks and reviews in press:

[67] Lanza A. F., Rodono M.: Magnetic activity and dynamics of close binaries, JENAM2003 “Minisymposium on Active Close Binaries”, K. G. Strassmeier and K. Olah(Eds.), Astronomische Nachrichten , in press

[68] Pagano I.: Real Time Observations with IUE Satellite from Vilspa, 25th Anniversaryof the Villafranca del Castillo Tracking Station of the European Space Agency, Vilspa,Madrid, 25 Nov 2003, in press

[69] Rodono M., Lanza, A. F.: Orbital motion and magnetic activity in close binariesand planetary systems, in IAU Symposium 219, “The Stars as Suns: activity, evolutionand planets”, A. K. Dupree and A. O. Benz (Eds.), ASP Conf. Ser. and IAU Publ.,San Francisco, in press

7.4 Contributions to international conferences

[70] Antonelli L. A., Zerbi F. M., Chincarini G., Ghisellini G., Rodono M., Tosti G.,Conconi P., Covino S., Cutispoto G., et al.: The REM telescope: a robotic facilityto monitor the prompt afterglow of gamma ray bursts, Memorie Societa AstronomicaItaliana 74, p. 304, 2003

[71] Antonuccio-Delogu V., Becciani U.,Ferro D., Romeo A.: A software interfacebetween Parallel Tree- and AMR Hydrocodes. Memorie della Societa Astronomica Ital-iana Supplement 1 , p. 109, 2003

7.4. CONTRIBUTIONS TO INTERNATIONAL CONFERENCES 119

[72] Barbieri C., Blanco C., Bucciarelli B., Coluzzi R., Di Paola A., Lanteri L., CausiG. Li L., Marilli E., Magrin S., Nesci R., Omizzolo A., Rampazzi F., Rossi C.,Stagni R., Viotti R.: Digitization of the Archives of Plates of the Italian AstronomicalObservatories and of the Specola Vaticana, Memorie della Societa Astronomica ItalianaSupplement 3, p.351, 2003

[73] Barstow, M.A., Binette, L., Brosch, N., Cheng, F.Z., Dennefeld, M., de Castro,A.I.G., Haubold, H., van der Hucht, K.A., Kappelmann, N., Martinez, P., Moisheev,A., Pagano I., Ribak, E.N., Sahade, J., Shustov, B.I., Solheim, J.-E., Wamsteker,W., Werner, K., Becker-Ross, H., Florek, S.:The WSO: a world-class observatory forthe ultraviolet, in ”Future EUV/UV and Visible Space Astrophysics Missions andInstrumentation”, J. Chris Blades, Oswald H. W. Siegmund (eds.), Proceedings of theSPIE 4854, p. 364-374, 2003

[74] Barstow M. A., and the WSO Team (Pagano I. enclosed): The World Space Obser-vatory , in “XIII European Workshop on White Dwarfs”, De Martino D., Silvotti R.,Solheim J.-E. & Kalytis R. eds., NATO Science Series, Kluwer Academic Publishers105, p. 407, 2003

[75] Becciani U., Antonuccio-Delogu V., Costa A., Ferro D.: FLY: A tree codetowards the adaptive mesh refinement, ASP Conf. Series 295, p. 423, 2003

[76] Becciani U. , Gheller, C. , Antonuccio- Delogu V., Ferro D. , Melotti, M.:AstroMD, a tool for Stereographic Visualization and data analysis for astrophysicaldata, Memorie della Societa Astronomica Italiana Supplement 1, p. 80, 2003

[77] Belvedere G., Kuzanyan K.M., Lanza A. F., Paterno L.: Asymptotic dynamo WaveModels of Magnetic Close Binaries with account of their evolutionary status, Proc.IAGA-IASPEI Joint Scientific Assembly, Hanoi, 19-31 August 2001, IAGA SessionG7.04, 2003

[78] Bernacca P. L., Antonello A., Preite Martinez A., Bertola F., Catalano S., RodonoM., Stalio R., Tondello G., Villa G. E., Buson L. M., et al.: Ultraviolet astronomyfrom the space station: A case study, in Recent Research Developments in Astronomy& Astrophysics 1, p. 75-109 , 2003

[79] Blanco C.: La Regione Piemonte contro l’inquinamento luminoso, Giornale di As-tronomia 29, N.1, p. 2, 2003

[80] Bonanno A., Belvedere G., Elstner D., Rudiger G.: Parity properties of an advec-tion dominated solar dynamo, 3rd meeting on the Solar Research in Italy, Vulcano,Sept. 30 - Oct. 4 , 2002, ed. by F. Zuccarello, D. Spadaro, R. Ventura, Memorie SocietaAstronomica Italiana 74, p. 542-546, 2003

[81] Bonanno A., Elstner D., Belvedere G., Rudiger G.: Advection dominated PositiveAlpha Dynamo in the Solar Convective Shell, Proc. IAGA-IASPEI Joint ScientificAssembly, Hanoi, 19-31 August, 2001, IAGA Session G7.04, 2003

[82] Bonanno G., Belluso M., Cosentino R., Scuderi S.: CMOS-APS Detectorsfor Astrophysical Applications, Memorie della Societa Astronomica Italiana 74, p.800, 2003


[83] Bortoletto R. F., D’Alessandro M., Fantinel D., Giro E., Corcione L., BonannoG., Bruno P., Cosentino R., Carbone A., Evola G.: A new generation of detectorcontroller , Memorie della Societa Astronomica Italiana, v. 74, p. 159, 2003

[84] Brucato J. R., Baratta G. A., Colangeli L., Mennella V., Strazzulla G.: Thermalannealing and ion irradiation processing: the structure of silicates dust, in “Astro-physics of Dust”, Estes Park, Colorado, May 26 - 30, 2003. Edited by Adolf N. Witt.,107B, 2003

[85] Busa I., Pagano I., Rodono M. , Gomez M. T., Andretta V., Terranegra L.: NLTEline-blanketed Ca II IRT calculation for evaluation of GAIA spectroscopic perfor-mances, ASP Conf. Ser. 298, p. 403, 2003

[86] Conconi P., Pareschi G., Antonello E., Scuderi S., Poletto L.: Multilayer coatingsfor the Ultraviolet Italian Sky Surveyor (UVISS) on the International Space Station,SPIE proceedings, Vol. 854, p. 397, 2003

[87] Contarino L. , Romano P., Zuccarello F. Yurchyshyn V. B.: A process of low-lyingmagnetic reconnection observed by THEMIS, BBSO and TRACE, in “3rd meeting onthe Solar Research in Italy”, Vulcano, Sept. 30 - Oct. 4 , 2002, ed. by F. Zuccarello,D. Spadaro, R. Ventura, Memorie Societa Astronomica Italiana 74, p. 647, 2003

[88] Costa A., Becciani U., Antonuccio-Delogu V. , Capuzzo Dolcetta R., MiocchiP. , Di Matteo P., Rosato V.: Astrocomp: web technologies for high performancecomputing on a grid of supercomputers, Memorie della Societa Astronomica ItalianaSupplement 1, p. 89, 2003

[89] Costa V., Iapichino L., Zappala R. A.: The P process in type II supernovae: currentstatus, Memorie Societa Astronomica Italiana, vol. 74, 466, 2003

[90] Covino S. , Zerbi F., Chincarini G., Ghisellini G. , Rodono M. ,Antonelli L. A.,Conconi P., Cutispoto G. , et al.: Monitoring of the Prompt GRB Afterglow withthe REM Telescope, in “GAMMA-RAY BURST AND AFTERGLOW ASTRONOMY2001”: A Workshop Celebrating the First Year of the HETE Mission. AIP ConferenceProceedings 662, p. 517-519, 2003

[91] Cutispoto G., Pagano I., Messina S.: CaII H & K char-acterization of COROT seismology primary targets, in “COROTWeek N.5”, Berlin 10-12 Dec 2003, electronic publication onhttp://berlinadmin.dlr.de/Missions/corot/cw5/contributions/cutispoto et al.pdf

[92] Di Matteo P., Miocchi P., Antonuccio-Delogu V., Becciani U., Dolcetta R. ,Costa A. , Rosato V.: AstroComp: a web portal for high-performance astrophysicalcomputing on a grid of supercomputers, ASP Conf. Series 295, p. 17, 2003

[93] Di Mauro M. P., Pijpers F., Christensen-Dalsgaard J., Paterno L., Teixera T.,Thompson M. J.: On the asteroseismic constraints for modeling the delta-Scuti starsV480TAU and theta2 TAUA, in “International Conference on magnetic fields in O,B and A stars. Origin and Connection to Pulsation, Rotation and Mass Loss”, ASPConference Series, Vol. N. 305, ed. by L. A Balona, H. F. Henrichs & T. Medupe, p.161-166, 2003


[94] Frasca A., Biazzo K., Catalano S., Marilli E.: Photospheric and ChromosphericActive Regions from Line Depth Ratios and H-alpha Emission, in “New Directions forClose Binary Studies: The Royal Road to the Stars.” Dardanos, Canakkale (Turkey),24-28 June, 2002, COMU Astrohysics Research Center, p. 173-183, 2003

[95] Frasca A., Aslan Z., Messina S., Catalano S.: Short and Long Term Chromo-spheric Activity in The Triple System DH Leonis, in “New Directions for Close BinaryStudies: The Royal Road to the Stars.” Dardanos, Canakkale (Turkey), 24-28 June,2002, p. 188-195, COMU Astrohysics Research Center, 2003

[96] Gheller C., Becciani U., Ferro D., Melotti M., Calori L.: The Cosmo. Lab project:developing AstroMD, an object oriented, open source visualization and pre-analysistool for astrophysical data, ASP Conf. Series, 295, 449, 2003

[97] Giro E., Bonoli C., Leone F. , Molinari E., Pernechele C., Zacchei A.: Polarizationproperties at the Nasmyth focus of the alt-azimuth TNG telescope in “Polarimetry inAstronomy” Ed. by Silvano Fineschi, SPIE 4843, p. 456-464, 2003.

[98] Lanza A. F., Rodono M., Pagano I., Barge P., Llebaria A.: Modelling the irradi-ance variations of the Sun as a star: first results and relevance for the simulations ofthe stellar activity, in Proceedings of the “4th COROT Week”, P. Barge (Ed.), LAM,Marseille http://www.astrsp-mrs.fr/projets/corot/meeting/cw4/cw4exop.html

[99] Lanzafame G., Costa V., Belvedere G.: SPH modelling of spiral shocks in viscousand inviscid accretion discs in close binary systems, in “Proc. IAU 8th Asian-PacificRegional Meeting Vol. II”, S. Ikeuchi, J. Hearnshaw, T. Hanawa eds., ASJ, p. 343,2003

[100] Leone F.: The High Resolution Spectropolarimeter of the Italian TelescopioNazionale Galileo, in “Solar Polarization 3”, ASP. Conf. Ser. 307, p. 51, 2003

[101] Leone F. , Bruno P., Calı A., Claudi R. , Cosentino R., Gentile G., Grat-ton R., Scuderi S.: High-Resolution Spectropolarimetry at the Telescopio NazionaleGalileo, in “ Polarimetry in Astronomy”. Edited by Silvano Fineschi . Proceedings ofthe SPIE, Volume 4843, p. 465-475 ,2003

[102] Linsky, J. L., Pagano, I., Valenti, J., Gagne, M., Duncan, D. K.: The Sun as aStar: Comparing α Cen A to UV Solar Spectra IAU Symposium 219, p. 224, 2003

[103] Magazzu A., Dougados C., Licandro J., Martın E. L., Magnier E., Menard F.:Infrared Spectra of Brown Dwarf Candidates in Taurus, Proceedings of the IAU Sym-posium 211, ”Brown Dwarfs”, ed. by E. L. Martin, held in Waikoloa, Hawaii, USA,20-24 May 2002, p. 75-78, 2003

[104] Magnier E. A., Dougados C., Menard F., Martın E. L., Magazzu A. : A DeepPhotometric Search for Substellar Mass Objects in Taurus, Proceedings of the IAUSymposium 211, ”Brown Dwarfs”, ed. by E. L. Martin, held in Waikoloa, Hawaii,USA, 20-24 May 2002, p. 71-74, 2003


[105] Messina S., Guinan E.F.: Starspots Cycle Phase and Rotational Photometric Pe-riod Variations of Young Solar-type Stars: Different Patterns of Correlation in “12thCambridge Workshop on Cool Stars, Stellar Systems, and the Sun.” Boulder, July 30th- August 3rd, 2001, University of Colorado, Alexander Brown, Graham M. Harper,Thomas R. Ayres (eds.), p.941-945, 2003

[106] Messina S., Cutispoto G., Rodono M.: REM (Rapid Eye Mount) robotic obser-vations to investigate Spot-induced against Planetary Transit-induced Brightness Vari-ations, poster paper in Proc. of 2nd Eddington workshop “Stellar Structure and Hab-itable Planet Finding”, Palermo 9-11 April 2003 ,ESA SP-538, F. Favata, S. Aigraineds., 2003, in press

[107] Messina S. , Rodono M. , Cutispoto G.: A systematic search of starspots cyclesby robotic observations at Catania Astrophysical Observatory, in Poster Proceedingsof the “First Potsdam Thinkshop on Sunspots and Starspots” May, 6-10 2002, K. GStrassmeier and A. Washuettl (Eds), AIP, p. 73-76, 2003

[108] Miglio A., Christensen-Dalsgaard J., Di Mauro M. P., Monteiro M. J. P. F. G,Thompson M. J.: Seismological analysis of the second Helium ionization zone of thestars, poster paper in ”Asteroseismology across the HR diagram” Porto , July 1-5,2002, Portugal, only on cdrom, ed by M. J. Thompson, M. S. Cunha, M. J. P. F. G.Monteiro, by Kluwer, Astrophysics and Space Science Series 284, Issue 1, p.537-540,2003

[109] Miocchi P., Antonuccio-Delogu V., Becciani U., Capuzzo Dolcetta R. , CostaA., Di Matteo P., Rosato V.: AstroComp: using the portal to perform astrophysicalN-body simulations, Memorie della Societa Astronomica Italiana Supplement 1 , p. 96,2003

[110] Nesci R., Barbieri C., Bucciarelli B., Blanco C., Dipaola R.,Coluzzi A., Greco V.,Magrin S., Marilli E., Omizzolo A., Pedichini F., Rampazzi F., Rossi C.: Digitizationand electronic distribution of the astronomical plate archives of Italian Astronomicalobservatories, Memorie della Societa Astronomica Italiana Supplement 3, p. 364, 2003

[111] Pagano I., Busa I., Cutispoto G., Lanza A. F., Lanzafame A. C.,Leto G., Messina S., Ribas I., Rodono M., and Ventura R.: Lookingfor nano-flares and stellar micro-variability as mechanisms for coronal heat-ing, in “COROT Week N.5”, Berlin 10-12 Dec 2003, electronic publication onhttp://berlinadmin.dlr.de/Missions/corot/cw5/contributions/pagano et al 1.pdf

[112] Pagano I., Lanza A. F., Rodono M.: Modelling the bolometric andnarrow-band variation of the Sun as a star as observed by VIRGO/SoHO,COROT Week N.5, Berlin 10-12 Dec 2003, electronic publication onhttp://berlinadmin.dlr.de/Missions/corot/cw5/contributions/pagano et al 2.pdf

[113] Pagano I.,Rodono M., Bonanno G., Buson L., Cassatella A., De Martino D.,Wamsteker W., Shustov B., Barstow M., Brosch N., Fu-Zhen C., Dennefeld M., Gomezde Castro A. I., Kappelmann N., Sahade J., Van der Hucht K., Solheim J.-E., Haubold


H., Altamore A., Andretta V., Badiali M., Becciani U., Busa I., Cappellaro E., Car-dini D., Catalano S., Castellani V.: The World Space Observatory Project WSO/UV,Memorie della Societa Astronomica Italiana Supplement, v.3, p.327, 2003

[114] Pallavicini R., Delabre B., Pasquini L., Zerbi F. M., Bonanno, G.; Comari M.,Conconi P., Mazzoleni R., Santin P., Damiani F., Di Marcantonio P., Franchini M.,Spano P., Bonifacio P., Catalano, S., Molaro P. P., Randich S., Rodono M.: TheAVES adaptive optics spectrograph for the VLT: status report , in: “Instrument De-sign and Performance for Optical/Infrared Ground-based Telescopes” Edited by Iye,Masanori; Moorwood, Alan F. M. Proceedings of the SPIE, Volume 4841, p. 715-726,2003

[115] Ragaini S. , Andretta V. , Gomez M. T. , Terranegra L. , Busa I. , Pagano I.:GAIA spectroscopy of active solar-type stars, ASP Conf. Ser. 298, U. Munari (ed), p.2003

[116] Romano P.,Contarino L., Zuccarello F.: Instability analysis of an active promi-nence,in “3rd meeting on the Solar Research in Italy”, Vulcano, Sept. 30 - Oct. 4 ,2002, ed. by F. Zuccarello, D. Spadaro, R. Ventura, Memorie Societa AstronomicaItaliana 74, p. 651, 2003

[117] Sciacca E. , A. , Giudice A. C. , Sanfilippo D. , Zappa F. , Lombardo S. , CosentinoR. , Di Franco D. , Ghioni M. , Fallica G. , Bonanno G. , Cova S. , Rimini E. :Silicon Planar Technology for Single-Photon Optical Detectors, IEEE Transactions onElectron Devices, Volume 50 n. 4, p. 918-925, 2003

[118] Smareglia R. , Pasian, F. Zacchei A. , Caproni A. , Longo G. , Becciani U. , GhellerC.: Archive systems for the TNG telescope: lessons learned in the VO perspective, in“ Virtual Observatories” Edited by Szalay, Alexander S., Proceedings of the SPIE,Volume 4846, p. 158-169, 2003

[119] Smareglia R., Becciani U., Caproni A., Gheller C., Guerra J. C., Lama N., LongoG., Pasian F., Zacchei A.: The Pilot Project for the TNG Long-Term Archive Sait2002, Memorie della Societa Astronomica Italiana, 74, p. 514, 2003

[120] Spadaro D., Lanza A. F.: Simulations of transiently heated solar coronal loop,in “3rd meeting on the Solar Research in Italy”, Vulcano, Sept. 30 - Oct. 4 , 2002, ed.by F. Zuccarello, D. Spadaro, R. Ventura, Memorie Societa Astronomica Italiana 74,p. 687, 2003

[121] Ternullo M. , Contarino L., Romano P., Zuccarello F.: The impact of the spot-group age and lifetime on their capability of hosting M and X flares, in “3rd meetingon the Solar Research in Italy”, Vulcano, Sept. 30 - Oct. 4 , 2002, ed. by F. Zuccarello,D. Spadaro, R. Ventura, Memorie Societa Astronomica Italiana 74, 615, 2003

[122] Testi L., Natta A., Baffa C., Comoretto G., Gennari S., Ghinassi F., Licandro J.,Magazzu A., Oliva E., D’Antona F.: An Efficient Low-Resolution NIR ClassificationScheme for M, L, and T dwarfs and Its Application to Young BDs, Proceedings of theIAU Symposium 211, “Brown Dwarfs”, ed. by E. L. Martin, held in Waikoloa, Hawaii,USA, 20-24 May 2002, p. 359-360, 2003


[123] Uslenghi M. C. , Bonanno G. , Belluso M. , Calı A., Timpanaro C. ,Cosentino R., Scuderi S. , Modica A.: Progress report on the photon countingintensified APS Future EUV-UV and Visible Space Astrophysics Missions and Instru-mentation, in Proceedings of SPIE Vol. 4854, p. 583, 2003.

[124] Villata M., Frasca A., Marilli E., Robb R. M.,Catalano S. et al.:The WholeEarth Blazar telescope on BL Lacertae, poster paper in “High Energy Blazar Astron-omy”, held 17-21 June 2002 at Tuorla Observatory, Piikkio, Finland, Leo O. Takaloand Esko Valtaoja (Eds.),ASP Conference Proceedings, Vol. 299, p. 221, 2003

[125] Vitali, F. , Zerbi, F. M. , Chincarini, G. , Ghisellini, G. , Rodono, M. , Tosti, G. ,Antonelli, L. A. , Conconi, P. , Covino, S. , Cutispoto, G. , et al.: The REM-IR cam-era: High quality near infrared imaging with a small robotic telescope, in Proceedingsof the SPIE, Volume 4841, pp. 627-638, 2003

[126] Zerbi, F. M. , Rodono, M., Tosti, G. , Antonelli, L. A. , Conconi, P. , Covino,S. , Cutispoto, G. , et al.: REM telescope, a robotic facility to monitor the promptafterglow of Gamma Ray Bursts, in Proceedings of the SPIE, Volume 4841, pp. 737-748, 2003

[127] Zuccarello F. , Contarino L. , Romano P. , Ternullo M.: Program of solar ob-servations and flare warning at Catania Astrophysical Observatory, Proc. of ”SpaceWeather Workshop” ESA WPP 194, 2003

[128] Zuccarello F., Zappala R.A.: Angular velocity of sunspot-groups during the activitycycle deduced using the age selection methodology, “3rd meeting on the Solar Researchin Italy”, Vulcano, Sept. 30 - Oct. 4 , 2002, ed. by F. Zuccarello, D. Spadaro, R.Ventura, Memorie Societa Astronomica Italiana 74, p. 619, 2003

[129] Pagano I., the Italian WSO/UV Working group, and the WSO/UV Implementa-tion Committee, 2003, eprint arXiv:astro-ph/0306554, The World Space ObservatoryProject (WSO/UV), Poster paper presented at the XLVII SAIt Meeting, Trieste 14-17April 2003

7.4.1 Contributions in press

[130] Barbieri C., Blanco C., Bucciarelli B., Coluzzi R., Di Paola A., Lanteri L., Causi G.L. Li, Marilli E., Massimino P., Mottola S., Nesci R., Omizzolo A., Pedichini F.,Rampazzi F., Rossi C., Stagni R., Tsvetkov M.,Viotti R. : Status of the digitizationof the Archives of Plates of the Italian Astronomical Observatories and of the SpecolaVaticana, in JENAM, Budapest 2003, in press

[131] Belluso M. , Bonanno G. , Calı A. , Carbone A. , Cosentino R. , ModicaA. , Scuderi S. , Timpanaro C., Uslenghi M.: A new photon Counting detector:Intensified CMOS-APS in “Scientific Detectors for Astronomy” - June 16-22, 2002 -Waimea, Hawaii, in press

[132] Blanco C., Bonanno G., Belluso M., Bruno P., Calı A.,Gandolfi D., Tim-panaro M. C.: CCD large area asteroidal photometric research, in “V Congresso


Nazionale di Scienze Planetarie”, Gallipoli (LE), 15-19 settembre 2003, Memorie So-cieta Astronomica Italiana, in press

[133] Brunetto R.,Baratta G. A., Strazzulla G.: Raman spectra of the Murchisonmeteorite, in “V Congresso Nazionale di Scienze Planetarie”, Gallipoli (LE), 15-19settembre 2003, Memorie Societa Astronomica Italiana, in press

[134] Catanzaro G.: Spectroscopic analysis of SB systems with HgMn components,in “Spectroscopic and spatially resolving the components of close binary stars”,Dubrovnik, 20 - 24 October 2003, Croatia, in press

[135] Costa V., Pumo M.L., Zappala R. A.: Uncertainty sources on the s-p process con-nection in massive stars (M > 10M), in Proceedings of the LXXXIX S.I.F. meeting,Parma, 17 - 22 September 2003, in press

[136] Cosentino R. , Belluso M. , Bonanno G. , Bruno P. , BortolettoF. , D’Alessandro M. , Fantinel D. , Giro E. , Corcione L. , Carbone A.,Evola G.: The new generation CCD controller: first results in “Scientific De-tectors for Astronomy” - June 16-22, 2002 - Waimea, Hawaii, HYPERLINK”http://sunct.ct.astro.it/rco/publi/no.pdf”, in press

[137] Cosentino R. , Belluso M. , Bonanno G. , Scuderi S., Di Franco C. , FallicaP. G., Sanfilippo D. , Sciacca E. , Lombardo S.: Preliminary test measurements ofSPAD array in “ Scientific Detectors for Astronomy” - June 16-22, 2002 - Waimea,Hawaii , in press

[138] Gratton R., Bonanno G, Bruno P., Calı A., Claudi R. U., Cosentino R.,Desidera S., Diego F., Farisato G., Martorana G., Rebeschini M., Scuderi S.: Sarg:The high resolution spectrograph of TNG Experimental Astronomy, Kluwer AcademicPublishers, EXPA459 , in press

[139] Gratton R., Carretta E., Claudi R. U., Desidera S., Lucatello S., Bonanno G.,Cosentino R. , Scuderi. S., Barbieri M., Marzari F., Endl M., Brocato E., DolciM, Valentini: The SARG Planet Search: hunting for planets around stars in widebinaries in “ Scientific Frontiers in Research on Extrasolar Planets”, Washington 18-22 June 2002 ASP Conf. Series, in press

[140] Guglielmino S., Palumbo M.E.: Spectral evidence of H2O trapped in N2 ice: acase for Pluto and Triton, in “V Congresso Nazionale di Scienze Planetarie”, Gallipoli(LE), 15-19 settembre 2003, Memorie Societa Astronomica Italiana, in press

[141] Lanza A. F., Rodono M., Pagano I., Barge P., Llebaria A.: Modelling the Rota-tional Modulation of the Total Solar Irradiance as Observed by VIRGO/SoHO, posterpaper in the 2nd Eddington workshop “Stellar Structure and Habitable Planet Find-ing”, Palermo 9-11 April 2003, F. Favata and S. Aigrain (Eds.), ESA-SP 538, 2004,p. 343 - 347

[142] Leone F.: The high resolution spectropolarimeter of the Italian TelescopioNazionale Galileo, in Third international workshop on ”SOLAR POLARIZATION”30th September- 4th October, 2002 Puerto de La Cruz, Tenerife, Spain , organized bythe Instituto de Astrofsica de Canarias, ASP Conf. Series, in press


[143] Massimino P., Greco V., Blanco C., Cigna M., Mangano A., Marilli E.:La digitalizzazione degli archivi di lastre astronomiche dell’OAC, Bollettino Atti Ac-cademia Gioenia , in press

[144] Omizzolo A., Barbieri C.,Blanco C., Bucciarelli B., Di Paola A., Nesci R.: Digitiza-tion of Archives of Astronomical Plates, in “Large Telescopes and Virtual Observatory:Visions for the Future”, 25th meeting of the IAU, Joint Discussion 8, 17 July 2003,Sydney, Australia, in press

[145] Strazzulla G., Baratta G. A., Leto G., Palumbo M. E., Spinella F.: Ionirradiation experiments relevant to planetology, in “V Congresso Nazionale di ScienzePlanetarie” Gallipoli (LE), 15-19 settembre 2003, Memorie Societa Astronomica Ital-iana, in press

[146] Weiss, W., Aert, C., Aigrain, S., .... Pagano, I.: Additional Science Potentialfor COROT, poster paper in Proc. 2nd Eddington Workshop ”Stellar Structure andHabitable Planet Finding”, Palermo, 9–11 April 2003, ESA SP-538, A. Wilson (ed.),2003, in press

7.4.2 Presentations without proceedings

[147] Bonanno G.: CCD Chracterization, in ”Alla ricerca di pianeti nella fascia diabitabilita”, E. Antonello, F. D’Antona, M. P. Di Mauro, G.Piotto, A. Preite Martinez(SOC), Monte Porzio Catone, INAF - OAR, 17-18 October 2003

[148] Di Mauro M. P.: Interpretation of the Solar-Like Behaviour of Eta Bootis con-tributed poster in “Solar and Solar-Like Oscillations: Insights and Challenges for theSun and Stars”, 25th meeting of the IAU, Joint Discussion 12, 18 July 2003, Sydney,Australia

[149] Di Mauro M. P.: Internal Structure of the Stars by studying pulsation propertiesin ”Alla ricerca di pianeti nella fascia di abitabilita”, E. Antonello, F. D’Antona, M. P.Di Mauro, G.Piotto, A. Preite Martinez (SOC), Monte Porzio Catone, INAF - OAR,17-18 October 2003

[150] Lanza A. F., Rodono M., Pagano I.: Stellar activity and surface rotation fromEddington photometry, in ”Alla ricerca di pianeti nella fascia di abitabilita”, E. An-tonello, F. D’Antona, M. P. Di Mauro, G. Piotto, A. Preite Martinez (SOC), MontePorzio Catone, INAF - OAR, 17-18 October 2003

7.5 Electronic publications, short articles and

technical reports

[151] Belluso M., Bonanno G., Bruno P., Calı A., Timpanaro M. C.: Sistema diacquisizione immagini per le osservazioni solari dell’Osservatorio Astrofisico di Cata-nia, INAF-OAC: Rapporti Tecnici N. 2/2003

ELECTRONIC AND SHORT ARTICLES, TECHNICAL REPORTS 127

[152] Cutispoto G., Messina S., Rodono M.: UBV(RI)c photometry of active stars.X. (Cutispoto+, 2003), VizieR On-line Data Catalog: J/A+A/400/659. Originallypublished in: 2003A&A...400..659C, 2003

[153] Lanza, A. F.: Origine ed evoluzione dell’Universo: gli ultimi sviluppi, atti degliincontri culturali organizzati dalla Biblioteca Diocesana S. Paolino di Nola, a cura di G.Santaniello e P. Scafuro, in Impegno e Dialogo 14, 151-163, Edizioni LER, Marigliano(NA), 2003

[154] Lanza A. F., Leto G. (Eds. ): INAF - OAC, Annual Report 2002

[155] Messina S., Guinan E.F.: Magnetic activity of 6 young solar stars. II(Messina+, 2003),VizieR On-line Data Catalog: J/A+A/409/1017. Originally pub-lished in:2003A&A...409.1017M, 2003

[156] Messina S., Pizzolato N., Guinan E.F., Rodono M.: X-ray emission in cool mainsequence stars (Messina+, 2003), VizieR On-line Data Catalog: J/A+A/410/671.Originally published in: 2003A&A...410..671M, 2003

[157] Pagano I., Linsky J.L. Valenti J. Duncan D.K., 2003, HST/STIS spectra of alpha-Cen A (Pagano+, 2004), VizieR On-line Data Catalog: J/A+A/415/331. Originallypublished in: 2004A&A...415..331P

[158] Zerbi F.M., Rodono M., Cutispoto G., Gentile, G. Martinetti E., MessinaS., Sardone S., et al.: GRB 031203: IR NTT observations do not confirm REMdetection, GRB Coordinates Network, Circular Service, 2471, 1, 2003

[159] Zerbi F.M., Rodono M., Cutispoto G., Gentile G., Martinetti E., Messina S.,Sardone S., et al.: GRB 031203: IR REM observations, GRB Coordinates Network,Circular Service, 2466, 1, 2003

Appendix A

Sommario del bilancio OACt 2003

La gestione del bilancio dell’ esercizio finanziario 2003, pi che negli anni precedenti stataimprontata alla massima attenzione al risparmio sulle spese di funzionamento ordinarioda una parte ed alla acquisizione di nuove attrezzature necessarie per il conseguimentodegli obbiettivi istituzionali dell’ OACt. L’attivit svolta ha incontrato serie difficolta inrelazione all’acquisizione di nuove attrezzature a parte quelle programmate su impegnidi bilancio degli anni precedenti. Nel complesso stata mantenuta ad altissimo livellodimostrato dai risultati conseguiti e illustrati in questo rapporto.

E’ da rilevare in via preliminare che, sia il bilancio preventivo che il conto consuntivodel 2003 in conformit all’ art. 23 del Regolamento sulla Amministrazione, contabilit eattivit contrattuale dell’ INAF stato richiesto che venisse gestito in termini di Cassa.

Il bilancio con la sua forma finale delle previsioni definitive delle entrate e delle spesesi realizzato apportando variazioni in diverse sedute del CdO, essenzialmente per rego-larizzare nuove entrate (UE, ASI, MIUR, INAF etc.) e per adeguare alcuni capitoli dispesa.

Analizzando la gestione di cassa si evince il seguente quadro delle entrate:La situazione amministrativa evidenzia la consistenza del fondo di cassa in 1.981.835,66

alla fine dell’esercizio finanziario 2003, come scaturisce dalla scritture contabili e in accordocon le risultanze dell’Istituto cassiere ed un avanzo di amministrazione, risultante dalladisponibilita di cassa alla chiusura dell’attivita e della somma algebrica dei crediti e deidebiti (impegni assunti entro al fine dell’anno, qui non riportati ma allegati al Contoconsuntivo).

Table A.1: Entrate (kEU)Entrate definitive Riscosse Da riscuotere

Fondo cassa 2.033 2.033Assegnazione funzion. 3.348 3.302 46Rimborsi e recuperi 583 574 9ASI 66 66Unione Europea 27 27Progetti COFIN 162 162Trasfer. da enti Pubblici 253 151 102Partite di giro 1.820 923 53Totale entrate 8.292 7.238 210

129

130 APPENDIX A. SOMMARIO DEL BILANCIO OACT 2003

Table A.2: Spese (kEU)Descrizione Previsioni definitive PagateSpese per Organi della strutt. 23 23Oneri per il Personale 3148 3090Spese per acquisto di beni e serv. 268 246Spese correnti per la ricerca 173 140Spese per la ricerca a dest. vincolata 501 221Oneri e tributi 12 12Spese diverse 4 4Acquisti e manut. straord. 42 30Spese di investim. per la ricerca 246 205Edilizia (impegni vincolati) 1.663 211Spese di invest. a dest. vincolata 407 112Rimborso mutui 5 5Partite di giro 1800 957Totale 8.292 5.256

Il fondo di cassa e essenzialmente costituito da fondi a destinazione vincolata (ASI,Regione, UE ecc.) e nella massima parte dalle assegnazioni e gli impegni di spesa inerentia lavori edilizi, la cui realizzazione e molto spesso frenata dai numerosi adempimentinecessari e dalla lentezza degli iter burocratici.

Dal semplice punto di vista economico, l’esercizio finanziario 2003 si e’ chiuso con unasignificativa riduzione dell’ avanzo di amministrazione. Cio e stato determinato da tre fat-tori principali: a) le maggiori spese intervenute a seguito dei lavori di ristrutturazione dell’edificio della sede di della citta universitaria (trasloco e affitto deposito, disattivazione ericonfigurazione impianti) b) acqquisizione di attrezzature per la ricerca da tempo pro-grammate e finalmente realizzate (es. il potenziamento dell’ impiantatore di ioni fino a200 kEv) c) l’ aumento dei prezzi

Mentre dai due maggiori fattori di spesa ci si aspetta delle ricadute positive in quantosi realizza da una parte un nuovo strumento di ricerca all’ avanguardia, e dall’ altra unsignificativo miglioramento degli ambienti di lavoro, la progressiva riduzione dell’ avanzodi amministrazione, accompagnata alla riduzione dei finanziamenti si riflette negativa-mente sulla possibilita di ulteriori miglioramenti delle attrezzature e delle strutture e sulmantenimento dell’ attivita di ricerca stessa agli attuali livelli di eccellenza.

Inoltre dalla analisi delle spese, da rilevare la forte incidenza delle spese per il person-ale, che globalmente ammonta al 94% del Fondo di Funzionamento Ordinario. La sommaresidua stata a malapena sufficiente a sopperire alle spese ordinarie senza possibilita di in-terventi significativi a livello di manutenzione, ed in qualche caso al ripristino adeguato diattrezzature guaste, con grave rischio di degrado del patrimonio dell‘Osservatorio e dellasua stessa funzionalita. Al fine di mantenere le spese di funzionamento entro le disponi-bilita di bilancio sono stati adottati dolorosi provvedimenti di riduzione della spesa. Iprovvedimenti adottati non hanno portato a risparmi significativi, in quanto gia le speseerano ridotti al minimo necessario ed hanno creato notevoli disagi sia tra il personaleche tra i fornitori di beni e servizi costretti a lavorare in condizioni minimi di guadagno.Inoltre hanno inciso negativamente sulla conduzione delle ricerche osservative presso lasede di Serra La Nave, per la perdita di continuita nei programmi di monitoring, e sulla

131

conduzione di osservazioni per tesi di laurea e di dottorato.

132 APPENDIX A. SOMMARIO DEL BILANCIO OACT 2003

inaf osservatorio astro sico di cataniaweb.ct.astro.it/report/rep2003/report03.pdf · inaf...

Documents