Cosmic ray acceleration in young supernova remnants

Understand

We investigate the appearance of magnetic field amplification resulting from a cosmic ray escape current in the context of supernova remnant shock waves.

• The current is inversely proportional to the maximum energy of cosmic rays, and is a strong function of the shock velocity.
• Depending on the evolution of the shock wave, which is drastically different for different circumstellar environments, the maximum energy of cosmic rays as required to generate enough current to trigger the non-resonant hybrid instability that confines the cosmic rays follows a different evolution and reaches different values.
• We find that the best candidates to accelerate cosmic rays to ~few PeV energies are young remnants in a dense environment, such as a red supergiant wind, as may be applicable to Cassiopeia A.