Possible Clustering of the Most Energetic Cosmic Rays within a Limited Space Angle Observed by the Akeno Giant Air Shower Array

Abstract

Accumulated data of the Akeno Giant Air Shower Array (AGASA) indicate that arrival directions of a significant fraction of extremely high energy cosmic rays (EHECR) are uniformly distributed over the observable sky. However, three pairs of showers with angular separation of less than 2.5 ± within the pair are observed among the 36 events above 40 EeV (4 3 10 19 eV), corresponding to a chance probability of 2.9% from uniform distribution. It should be noted that two pairs of them are observed to be within 2.0 ± of the supergalactic plane. [S0031-9007 (96)00833-2] PACS numbers: 98.70.Sa, 95.85.Ry, 98.65.Cw

High Energy Cosmic-Rays and Neutrinos from Cosmological Gamma-Ray Burst Fireballs

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Violation of the Greisen-Zatsepin-Kuzmin Cutoff: A Tempest in a (Magnetic) Teapot? Why Cosmic Ray Energies above1020eVMay Not Require New Physics

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