Nonthermal Particle Acceleration at Highly Oblique Nonrelativistic Shocks

The nonthermal acceleration of electrons and ions at an oblique, nonrelativistic shock is studied using large-scale particle-in-cell simulations in one spatial dimension. Physical parameters are selected to highlight the role of electron preheating in injection and subsequent acceleration of particles at high Mach number shocks. Simulation results show evidence for the early onset of the diffusive shock acceleration process for both electrons and ions at a highly oblique subluminal shock. Ion acceleration efficiencies of ≲5% are measured at late times, though this is not the saturated value.