Particle acceleration at modified shock fronts. II - The problem of injection
Abstract
This is the second paper in which a method is developed by which the transport and acceleration of cosmic ray particles in one-dimensional plasma flows can be treated without recourse to the diffusion approximation. Whereas the first paper concentrated on cosmic ray distribution functions which have the form of a power law in momentum, this paper extends the method to treat an arbitrary momentum distribution, using a partially implicit numerical method to integrate the transport equation from low to high momentum. The results indicate that the diffusion approximation overestimates the efficiency of the injection process at nonrelativistic shocks. The distribution function at mildly suprathermal speeds is found to be highly anisotropic. The importance of this result for 'self-consistent' models of the injection process is discussed.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1989
- Bibcode:
- 1989A&A...225..559K
- Keywords:
-
- Cosmic Rays;
- Magnetohydrodynamic Flow;
- One Dimensional Flow;
- Particle Acceleration;
- Shock Fronts;
- Anisotropy;
- Distribution Functions;
- Eigenvalues;
- Numerical Integration;
- Shock Waves;
- Astrophysics