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arXiv · 2211.07194

Thresholdless stochastic particle heating by a single wave

F. Sattin·D. F. Escande
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Abstract

Stochastic heating is a well-known mechanism through which magnetized particles may be energized by low-frequency electromagnetic waves. In its simplest version, under spatially homogeneous conditions, it is known to be operative only above a threshold in the normalized wave amplitude, which may be a demanding requisite in actual scenarios, severely restricting its range of applicability. In this work we show, by numerical simulations supported by inspection of the particle Hamiltonian, that allowing for even a very weak spatial inhomogeneity completely removes the threshold, trading the requirement upon the wave amplitude with a requisite upon the duration of the interaction between wave and particle. The thresholdless chaotic mechanism considered here is likely to be applicable to other inhomogeneous systems.

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F. Sattin, D. F. Escande. 2022-11-14. Thresholdless stochastic particle heating by a single wave. https://doi.org/10.1103/physreve.107.065201

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