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arXiv · 2202.07015

Underdense relativistically thermal plasma produced by magnetically assisted direct laser acceleration

K. Weichman·J. P. Palastro·A. P. L. Robinson·A. V. Arefiev
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Abstract

We introduce the first approach to volumetrically generate relativistically thermal plasma at gas-jet--accessible density. Using fully kinetic simulations and theory, we demonstrate that two stages of direct laser acceleration driven by two laser pulses in an applied magnetic field can heat a significant plasma volume to multi-MeV average energy. The highest-momentum feature is 2D-isotropic, persists after the interaction, and includes the majority of electrons, enabling experimental access to bulk-relativistic, high-energy-density plasma in an optically diagnosable regime for the first time.

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K. Weichman, J. P. Palastro, A. P. L. Robinson, A. V. Arefiev. 2022-02-14. Underdense relativistically thermal plasma produced by magnetically assisted direct laser acceleration. https://arxiv.org/abs/2202.07015

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