The American Astronomical Society, find out more The Institute of Physics, find out more Search for Large-scale Anisotropy on Arrival Directions of Ultra-high-energy Cosmic Rays Observed with the Telescope Array Experiment
The Astrophysical Journal Letters
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.
Abbasi, Rasha U., "The American Astronomical Society, find out more The Institute of Physics, find out more Search for Large-scale Anisotropy on Arrival Directions of Ultra-high-energy Cosmic Rays Observed with the Telescope Array Experiment" (2020). Physics: Faculty Publications and Other Works. 64.
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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