Proton Acceleration in Weak Quasi-parallel Intracluster Shocks: Injection and Early Acceleration

Ji-Hoon Ha, Dongsu Ryu, Hyesung Kang +1

Collisionless shocks with low sonic Mach numbers, $M_{\mathrm{s}}\lesssim 4$, are expected to accelerate cosmic ray (CR) protons via diffusive shock acceleration (DSA) in the intraclus…