Non‐linear particle acceleration at non‐relativistic shock waves in the presence of self‐generated turbulence

INAF – Osservatorio Astrofisico di Arcetri, Largo E. Fermi, 5, 50125, Firenze, Italy
Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.52). 09/2006; 371(3):1251 - 1258. DOI: 10.1111/j.1365-2966.2006.10739.x

ABSTRACT Particle acceleration at astrophysical shocks may be very efficient if magnetic scattering is self-generated by the same particles. This non-linear process adds to the non-linear modification of the shock due to the dynamical reaction of the accelerated particles on the shock. Building on a previous general solution of the problem of particle acceleration with arbitrary diffusion coefficients, we present here the first semi-analytical calculation of particle acceleration with both effects taken into account at the same time; charged particles are accelerated in the background of Alfvén waves that they generate due to the streaming instability, and modify the dynamics of the plasma in the shock vicinity.

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