Invited Presentation

Particle acceleration at shocks in galaxy clusters and large-scale structure

Author(s): Hyesung Kang (Pusan National University), Dongsu Ryu (UNIST), Ji-Hoon Ha (UNIST)

Presenter: Hyesung Kang (Pusan National University)

Weak shocks with sonic Mach number M_s <4 expected to form in the intracluster medium (ICM) during the course of hierarchical clustering of the large-scale structure of the Universe. The presence of such shocks has been established by X-ray and radio observations of many merging clusters. As for Earth's bowshocks and supernova remnant shocks, ICM shocks are thought to accelerate cosmic ray (CR) protons and electrons via diffusive shock acceleration (DSA). Although the acceleration of relativistic electrons by putative shocks has been observed as the so-called radio relics, the presence of CR protons produced by ICM shocks has yet to be confirmed. We will report our recent studies on the DSA acceleration efficiency at low Mach shocks in high beta ICM plasma.