Shock-accelerated cosmic rays and streaming instability in the adaptive mesh refinement code Ramses

Understand

Cosmic rays (CRs) are thought to play a dynamically important role in several key aspects of galaxy evolution, including the structure of the interstellar medium, the formation of galactic winds, and the non-thermal pressure support of halos.

• We introduce a numerical model solving for the CR streaming instability and acceleration of CRs at shocks with a fluid approach in the adaptive mesh refinement code ramses.
• CR streaming is solved with a diffusion approach and its anisotropic nature is naturally captured.
• We introduce a shock finder for the ramses code that automatically detects shock discontinuities in the flow.