Collisionless ion-electron energy exchange in magnetized shocks
Phys. Rev. E 113, 035205 – Published 10 March, 2026
DOI: https://doi.org/10.1103/16zv-35kt
Abstract
Energy partition between ions and electrons in collisionless shocks has been a long-standing unsolved fundamental physical question. We show that kinetic simulations of moderate Alfvénic Mach number, magnetized, collisionless shocks reveal rapid, faster-than-Coulomb, energy exchange between ions and electrons when the plasma is sufficiently magnetized. Using kinetic and multifluid models with counter-streaming ions, we identify resonances between electron whistler and ion magnetohydrodynamic waves that account for this rapid energy exchange.