oag common proper motions wide pairs survey
DESCRIPTION
OAG COMMON PROPER MOTIONS WIDE PAIRS SURVEY. II MEETING DOUBLE STAR OBSERVERS (Pro-Am) Sabadell 23-24 October 2010 Xavier Miret / Tòfol Tobal Observatori Astronòmic del Garraf (OAG) www.oagarraf.net. OAG CPM WPS. - PowerPoint PPT PresentationTRANSCRIPT
OAG COMMON PROPER MOTIONS WIDE PAIRS SURVEY
II MEETING DOUBLE STAR OBSERVERS
(Pro-Am)
Sabadell
23-24 October 2010
Xavier Miret / Tòfol TobalObservatori Astronòmic del Garraf (OAG)
www.oagarraf.net
OAG CPM WPS
Project: Search and detection of star pairs with CPM not catalogued yet.
FEATURES:
VISUAL SURVEY. Visual inspection of digitized plates.
SYSTEMATIC SURVEY. Scanning selected areas.
HISTORICAL BACKGROUND
W.J. Luyten Main contribution to
double stars with CPM Year 1979 NLTT > 58.000 stars LDS > 6.000 pairs μ > 0.2 arcsec yr -1
HISTORICAL BACKGROUND
Lépine & Shara SUPERBLINK
software. 2003-2008 LSPM > 122.000 > 1000 doubles μ > 0,15 arcseg yr -1
HISTORICAL BACKGROUND
GARRAF SURVEY (2008).
Search for companions of near 2.000 NLTT between 0,5 and 1 arcseg yr -1
J. A. Caballero &
D. Montes
GARRAF SURVEY LUYTEN STARS
STARS TO STUDY
Stellar population with CPM < 0,15
arcsec yr -1 not studied up to now.
Some pairs with CPM > 0,15 arcsec yr -1
not catalogued before.
COORDINATION & TEAMS
Coordination OAG.
Collaboration AAS. C. Schnabel.
Open information: www.oagarraf.net
OAG CPMWP SURVEY Workshop I & II
February and July 2010, Sabadell (Barcelona)
Tutorials. Method Techniques Practical examples
Resolution of questions. Adjudication sectors. Timetable. Preparation of publications.
Organization: OAG / AAS
CURRENT STATUS
> 500 pairs catalogued up to now. 10 amateur teams on work. Forecast: 12 h RA at the end 2010.
METHOD Loading images POSS I and POSS II (15 x 15 arcmin).
Δt +/- 40 years.
Blinking RGB. Identification of pairs.
Crossing catalogues. USNOB1 and NOMAD1.
Collecting data.
Polar coordinates. Theta/Rho. Aladin vector tool.
LOADING IMAGES
BLINKING RGB
BLINKING RGB
BLINKING RGB
CROSSING CATALOGUES
POLAR COORDINATES Theta/Rho measures on digitized plates. Optimization centroid (Image convolution). Aladin vector tool (Manual path). Reference. I Novalbos communication.
TARGETS Pairs with sep > 5”. No superior limit.
No magnitude limit.
PM > 50 marcsec y -1 in at least one coordinate.
Maximum difference in PM between components < 10 marcsec y -1 in two coordinates. ◄
TARGETS ¿What is the proper motions difference between components? Always < 15% the absolute value of PM Always < 3 X mean error (catalogue value)
DATA COLLECTION 1
IDENTIFICATION. USNOB1 / NOMAD1 / 2MASS / TYCHO2 / HIPPARCOS
RA / DEC J2000 MAGNITUDE V or R PM RA PM DEC PM CATALOGUE SOURCE
DATA COLLECTION 2 THETA RHO EPOCH In case of lack of PM in pairs with
suggestive image blinking we make multiepoch astrometry to support the CPM character.
MULTIEPOCH ASTROMETRY
RESULTS. MAGNITUDE.
MAG R MAG (nº Stars) V MAG (nº Stars)
8 - 10 1 7
10 -12 15 27
12 -14 29 43
14 -16 46 66
16 -18 42 91
18 - 20 20 0
RESULTS PROPER MOTIONSSAMPLE 187 PAIRS
CPM marcsec y-1 Number Stars
50 - 75 90 (48.1 %)
76 - 100 62 (33,1 %)
101 - 125 26 (13.9%)
126 - 150 7 (3.7%)
151 - 200 2 (1%)
PUBLICATION
Revision and cataloguing USNO / WDS: B.D.Mason (USNO).
Electronic publication: USNO/WDS Website Publication: Webb Society DSSC: B.Argyle Professional studies and publications.
J. A.Caballero , D. Montes.
FUTURE Encourage professional and amateur teams
interested so that the project can be improved.
Searching and development a software capable to find the same pairs automatically.
Stellar characterization in at least some subgroups of stars.
Observatori Astronòmic del GarrafParc del Garraf (Barcelona)