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arXiv · 2102.05499

Weibel instability beyond bi-Maxwellian anisotropy

Thales Silva·Bedros Afeyan·Luis O. Silva
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Abstract

The shape of the anisotropic velocity distribution function, beyond the realm of strict Maxwellians can play a significant role in determining the evolution of the Weibel instability dictating the dynamics of self-generated magnetic fields. For non-Maxwellian distribution functions, we show that the direction of the maximum growth rate wavevector changes with shape. We investigate different laser-plasma interaction model distributions which show that their Weibel generated magnetic fields may require closer scrutiny beyond the second moment (temperature) anisotropy ratio characterization.

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Thales Silva, Bedros Afeyan, Luis O. Silva. 2021-02-10. Weibel instability beyond bi-Maxwellian anisotropy. https://doi.org/10.1103/physreve.104.035201

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