Full-Sky Search for Ultra High Energy Cosmic Ray Anisotropies

Abstract

Using data from the SUGAR and the AGASA experiments taken during a 10 yr period with nearly uniform exposure to the entire sky, we search for large-scale anisotropy patterns in the arrival directions of cosmic rays with energies > 10^{19.6} eV. We determine the angular power spectrum from an expansion in spherical harmonics for modes out to \ell=5. Based on available statistics, we find no significant deviation from isotropy. We compare the rather modest results which can be extracted from existing data samples with the results that should be forthcoming as new full-sky observatories begin operation.

v1. To appear in the Proceedings of the 28th International Cosmic Ray Conference, at http://www.icrr.u-tokyo.ac.jp/icrc2003/. v2. More detailed paper, submitted for publication. v3. Final version, to be published in Phys. Rev. D

References in corpus (2)

• Ultrahigh Energy Cosmic Rays: The state of the art before the Auger Observatory
• Large Scale Magnetic Fields and the Number of Cosmic Ray Sources above 10^(19) eV

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