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arXiv · 2509.05518

Perpendicular ion heating in turbulence and reconnection: magnetic moment breaking by coherent fluctuations

Alfred Mallet·Kristopher G. Klein·Benjamin D. G. Chandran·Tamar Ervin·Trevor A. Bowen
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Abstract

We study the interaction of an ion with a fluctuation in the electromagnetic fields that is localized in both space and time. We study the scale-dependence of the interaction in both space and time, deriving a generic form for the ion's energy change, which involves an exponential cutoff based on the characteristic timescale of the electromagnetic fluctuation. This leads to diffusion in energy in both $v_\perp$ and $v_\parallel$. We show how to apply our results to general plasma physics phenomena, and specifically to Alfv\'enic turbulence and to reconnection. Our theory can be viewed as a unification of previous models of stochastic ion heating, cyclotron heating, and reconnection heating in a single theoretical framework.

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Alfred Mallet, Kristopher G. Klein, Benjamin D. G. Chandran, Tamar Ervin, Trevor A. Bowen. 2025-09-05. Perpendicular ion heating in turbulence and reconnection: magnetic moment breaking by coherent fluctuations. https://doi.org/10.1017/s0022377825101177

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