Updates on the Hotspot and the Perseus-Pisces supercluster Excess Observed by the Telescope Array Experiment

¹ High Energy Astrophysics Institute and Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112-0830, USA
² Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan

^* Corresponding author: jihyun@cosmic.utah.edu

Published online: 28 April 2023

Abstract

The Telescope Array (TA) experiment, the largest observatory studying ultra-high energy cosmic rays in the northern hemisphere, has reported evidence for two medium-scale anisotropies. The first, known as the TA hotspot, is an excess in the arrival direction distribution for events with energies greater than 5.7 × 10¹⁹ eV. More recently, an additional excess of events with energies greater than 10^19.4 eV appearing in the direction of the Perseus-Pisces supercluster has been named the PPSC excess. In this presentation, we will update the status of the TA hotspot and the PPSC excess results using the most recent data measured by the TA surface detector array.