Ultra High Energy Cosmic Ultra High Energy Cosmic Rays Anisotropies and Rays Anisotropies and

Astrophysical InterpretationAstrophysical Interpretation

Alessandro Cuoco,Institute for Physics and

Astronomy University of Aarhus,

Denmark

May 21th 2008 XXth RENCONTRES

DE BLOIS

Sky Distribution•For E>4-5 x1019 eV galactic and extragalactic magnetic fields are negligible and charged particles propagate almost rectilinearly: is it possible UHECRs astronomy?

•Energy losses impose that sources must be near (100-200 Mpc) (GZK Cutoff)

•Data from AGASA (50 events) indicate an isotropic distribution (extragalactic origin) except for a small scale clustering (point sources?)…

Auger & HIRES… GZK cutoff?!?!

AUGER ICRC07:Vertical+Inclined+Hyb

rid6σ Feature

Hires ICRC07:5σ Feature

Local Universe (Eq. Coordinates)

Looking for structures in UHECRsLooking for structures in UHECRs

M. Kachelriess & D. Semikoz Astropart. Phys. 26, 10 (2006) [astro-ph/0512498]

The rescaling is done a priori, to match the ankle feature in the spectrum

World dataset of O(100) public available UHECRs, above the “rescaled” energy of 4x1019 eV (Hires Scale)

“Both the energy dependence of the signal and its angular scale might be interpreted as first signatures of the large-scale structure of UHECR sources and of intervening magnetic fields”

Can we test that?

Some low-chance Some low-chance prob. Structure at prob. Structure at 1515oo-35-35oo!!!!!!

Clustering properties agree but structures do

not match…

Possible evidence for nearby universe structures in the ultra-high energy sky !

A.C., G. Miele, P.Serpico, PLB 660:307-314,2008,

arXiv:0706.2864

Check with PSCz: SH modelCheck with PSCz: SH model

The clustering properties of the data agree wonderfully with the SH model (chance probability of obtaining similar configurations ≈ 50%)

Not strange, after a look at the data

A.C., G. Miele, P.Serpico, PLB 660:307-314,2008 arXiv:0706.2864

Possible evidence for nearby universe structures in the ultra-high energy sky !

Auger AGNs CorrelationAuger AGNs Correlation

20 out of 27 events correlate with a nearby (within 75 Mpc) AGN within 3 degrees.

Remarkably, 5 out 7 non-correlating events lie on the galactic plane where the catalogue is incomplete and the highest deflections are

expected

Centaurus ACentaurus A

Auger Collaboration, Science, 318 (5852), 938 (2007); Auger Collaboration, Astropart.Phys.29:188-204,(2008) [arXiv:0712.2843].

AGN vs GalaxiesAGN vs Galaxies

IRAS Galaxies

Veron Cetty AGN Catalogue

Same large scale pattern but different

small scale clustering

A.C., S.Hannestad, T.Haugbølle, M.Kachelriess, P.Serpico arXiv:0709.2712, ApJ .676:807,2008

Auger AutoCorrelation

Auger AutoCorrelation compared to various model expectations

Chance probability for various models

Extragalactic Magnetic Fields

Powerful test for extra-galactic magnetic fields, very poorly known at the moment…

Worth testing!

Map of deflection Map of deflection angles from the local angles from the local

clustersclusters

CR deflection in random MF:

Auger Constrain on EGMFs:

Dolag et al. JCAP 0501:009,2005

Typical deflection maps for protonsTypical deflection maps for protons

• Larger deflections along the Galactic plane• Typical deflections around 5o

• Possible peculiar features in the bulge & haloTT

HMRPS

M. Kachelrieß, P.Serpico, M. Teshima Astrop. Phys.26, 378 [astro-ph/0510444]

E=4x1019 eV

Example of map-distortion by GMFExample of map-distortion by GMF

A.C., G. Miele, P.Serpico PLB 660:307-314,2008

Example of map-distortion by GMFExample of map-distortion by GMF

Check with PSCz: cross-correlationCheck with PSCz: cross-correlationPresence of structures

No significant cross-correlation

Also, for light nuclei both the auto-correlation and x-correlation are robust with respect to corrections in the GMF (checked 3 models and 3 “effective rigidities”)

Yet the chance probability drops from 50% to 10-15% for the SH model, for x-correlations within 50o

No statistical relevance, but reasonable for intermediate-heavy nuclei in the GMF and/or for protons with significant extragalactic deflections.

Relevant role of magnetic fields

AGN Engines

VLA: Radio Lobes

Chandra: X-ray Jets

Radio Sky

Hubble: Optical Dust Lane

CENTAURUS A

The IceCube Detector

Neutrinos from Cen A

: ~ 0.4-0.6 events/year

A.C., S.Hannestad, arXiv:0712.1830

Gamma emission: See talk of M.Kachelriess...

SummarySummary

Possibility of study of Galactic & Extra-Galactic Magnetic fields and single UHECRs sources: UHECR Astronomy

Strong hints of LSS anisotropy seen in Pre-Auger data.

Correlation with LSS (possibly AGNs) in the Auger data.

Possibility of multimessenger observations of sources with gammas, neutrinos and UHECRs