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arXiv · 1210.2643

The impact of kinetic effects on the properties of relativistic electron-positron shocks

A. Stockem·F. Fiuza·R. A. Fonseca·L. O. Silva
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Abstract

We assess the impact of non-thermally shock-accelerated particles on the magnetohydrodynamic (MHD) jump conditions of relativistic shocks. The adiabatic constant is calculated directly from first principle particle-in-cell simulation data, enabling a semi-kinetic approach to improve the standard fluid model and allowing for an identification of the key parameters that define the shock structure. We find that the evolving upstream parameters have a stronger impact than the corrections due to non-thermal particles. We find that the decrease of the upstream bulk speed yields deviations from the standard MHD model up to 10%. Furthermore, we obtain a quantitative definition of the shock transition region from our analysis. For Weibel-mediated shocks the inclusion of a magnetic field in the MHD conservation equations is addressed for the first time.

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A. Stockem, F. Fiuza, R. A. Fonseca, L. O. Silva. 2012-10-09. The impact of kinetic effects on the properties of relativistic electron-positron shocks. https://doi.org/10.1088/0741-3335%2F54%2F12%2F125004

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