Utra-High-Energy Cosmic Rays and Filaments of Galaxies

Abstract

Ultra-high-energy cosmic rays (UHECRs) are particles of extreme energies, coming from outside of our Galaxy. The Telescope Array (TA) experiment recently identified a high concentration in the arrival directions of UHECR events, called hotspot, but the nature and origin of the hotspot is still unknown. Recently in a paper paper, we reported the presence of filaments of galaxies, connected to the Virgo Cluster, on the sky around the hotspot. Based on it, we suggested a model for the origin of TA hotspot events; they are produced at sources in the Virgo Cluster, and escape to and propagate along filaments, before they are scattered toward us. In this talk, I present this work.