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arXiv · 1311.5207

Vortical field amplification and particle acceleration at rippled shocks

F. Fraschetti
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Abstract

Supernova Remnants (SNRs) shocks are believed to accelerate charged particles and to generate strong turbulence in the post-shock flow. From high-energy observations in the past decade, a magnetic field at SNR shocks largely exceeding the shock-compressed interstellar field has been inferred. We outline how such a field amplification results from a small-scale dynamo process downstream of the shock, providing an explicit expression for the turbulence back-reaction to the fluid whirling. The spatial scale of the $X-$ray rims and the short time-variability can be obtained by using reasonable parameters for the interstellar turbulence. We show that such a vortical field saturation is faster than the acceleration time of the synchrotron emitting energetic electrons.

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F. Fraschetti. 2013-11-18. Vortical field amplification and particle acceleration at rippled shocks. https://doi.org/10.1016/j.nima.2013.11.066

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