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arXiv · 2312.08564

Collisionless cooling of perpendicular electron temperature in the thermal quench of a magnetized plasma

Yanzeng Zhang·Jun Li·Xianzhu Tang
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Abstract

Thermal quench of a nearly collisionless plasma against a cooling boundary or region is an undesirable off-normal event in magnetic fusion experiments, but an ubiquitous process of cosmological importance in astrophysical plasmas. There is a well-known mismatch that what experimentally diagnosed is the drop in perpendicular electron temperature $T_{e\perp},$ but the parallel transport theory of ambipolar-constrained tail electron loss produces parallel electron temperature $T_{e\parallel}$ cooling. Here two collisionless mechanisms, dilutional cooling by infalling cold electrons and wave-particle interaction by two families of whistler instabilities, are shown to enable fast $T_{e\perp}$ cooling that closely tracks the mostly collisionless crash of $T_{e\parallel}.$

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Yanzeng Zhang, Jun Li, Xianzhu Tang. 2023-12-13. Collisionless cooling of perpendicular electron temperature in the thermal quench of a magnetized plasma. https://doi.org/10.1038/s41598-024-73968-7

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