E-resources
PDF-
Abbasi, R U; Abe, M; Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A
Astrophysical journal. Letters, 08/2014, Volume: 790, Issue: 2Journal Article
We have searched for intermediate-scale anisotropy in the arrival directions of ultrahigh-energy cosmic rays with energies above 57 EeV in the northern sky using data collected over a 5 yr period by the surface detector of the Telescope Array experiment. We report on a cluster of events that we call the hotspot, found by oversampling using 20degrees radius circles. The hotspot has a Li-Ma statistical significance of 5.1sigma, and is centered at R.A. = 146degrees.7, decl. = 43degrees.2. The position of the hotspot is about 19degrees off of the supergalactic plane. The probability of a cluster of events of 5.1sigma significance, appearing by chance in an isotropic cosmic-ray sky, is estimated to be 3.7 x 10 super(-4) (3.4sigma).
