Electron heating at quasi-perpendicular collisionless shocks

Ahmad Lalti; Yuri V. Khotyaintsev; Daniel B. Graham

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arXiv · 2402.16564

Electron heating at quasi-perpendicular collisionless shocks

Ahmad Lalti·Yuri V. Khotyaintsev·Daniel B. Graham

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Abstract

Adiabatic and non-adiabatic electron dynamics have been proposed to explain electron heating across collisionless shocks. We analyze the evolution of the suprathermal electrons across 310 quasi-perpendicular shocks with $1.7<M_A<48$ using in-situ measurements. We show that the electron heating mechanism shifts from predominantly adiabatic to non-adiabatic for the Alfv\'enic Mach number in the de Hoffman-Teller $\gtrsim 30$ with the latter constituting 48\% of the analyzed shocks. The observed non-adiabatic heating is consistent with the stochastic shock drift acceleration mechanism.

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Ahmad Lalti, Yuri V. Khotyaintsev, Daniel B. Graham. 2024-02-26. Electron heating at quasi-perpendicular collisionless shocks. https://arxiv.org/abs/2402.16564

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