How do supernova remnants accelerate cosmic rays?

Supernova remnants accelerate cosmic rays primarily through their powerful, expanding shock waves. As these remnants expand into the surrounding interstellar medium, they generate violent shocks and magnetic turbulence that can accelerate electrons and atomic nuclei to cosmic-ray energies, ranging from ${10}^9$ to ${10}^{15}$ electron volts per particle.12

While it is widely accepted that particle acceleration occurs via these expanding shock waves, the specific details of the processes involved in this production remain a subject of ongoing scientific study. Additionally, some supernova remnants contain pulsars—rapidly rotating, highly magnetized neutron stars—which also contribute to the acceleration of charged particles to velocities near the speed of light. It is believed that the majority of galactic cosmic rays originate from these supernova events and their associated remnants.13