Document Type

Article

Publication Date

7-27-2020

Publication Title

The Astrophysical Journal Letters

Volume

898

Issue

2

Publisher Name

IOP Publishing

Abstract

Motivated by the detection of a significant dipole structure in the arrival directions of ultra-high-energy cosmic rays above 8 EeV reported by the Pierre Auger Observatory (Auger), we search for a large-scale anisotropy using data collected with the surface detector array of the Telescope Array Experiment (TA). With 11 yr of TA data, a dipole structure in a projection of the R.A. is fitted with an amplitude of 3.3% ± 1.9% and a phase of 131° ± 33°. The corresponding 99% confidence-level upper limit on the amplitude is 7.3%. At the current level of statistics, the fitted result is compatible with both an isotropic distribution and the dipole structure reported by Auger.

Comments

Author Posting © AAS, 2020. This article is posted here by permission of AAS. All rights reserved. The article was published in The Astrophysical Journal Letters, Volume 898, Issue 2, July 2020, https://doi.org/10.3847/2041-8213/aba0bc

Included in

Physics Commons

Share

COinS