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DOE OSTI · 3022852

Collisionless ion-electron energy exchange in magnetized shocks

Zhang, Y. [University of Rochester, NY (United States)] (ORCID:0000000310177953)·Heuer, P. V. [University of Rochester, NY (United States)] (ORCID:0000000150506606)·Wen, H. [University of Rochester, NY (United States)] (ORCID:000000018567380X)·Davies, J. R. [University of Rochester, NY (United States)] (ORCID:0000000182338272)·Ren, C. [University of Rochester, NY (United States)] (ORCID:0000000208584827)·Schaeffer, D. B. [University of California-Los Angeles, CA (United States)] (ORCID:0000000316755910)·Blackman, E. G. [University of Rochester, NY (United States)]·Zhang, J. [University of Rochester, NY (United States)]·Bret, A. [Universidad de Castilla-La Mancha, Ciudad Real (Spain); Campus Universitario de Ciudad Real (Spain)] (ORCID:0000000320300046)·García-Rubio, F. [Pacific Fusion Corporation, Fremont, CA (United States)] (ORCID:0000000271683190)
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Abstract

Energy partition between ions and electrons in collisionless shocks has been a long-standing unsolved fundamental physical question. Here, we show that kinetic simulations of moderate Alfv´enic 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 multi-fluid models with counter-streaming ions, we identify resonances between electron whistler and ion magnetohydrodynamic waves that account for this rapid energy exchange.

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High-energy-density plasmasLaboratory studies of space & astrophysical plasmasMagnetohydrodynamicsPlasma instabilitiesSpace & astrophysical plasmaSpace scienceWave-wave, wave-particle interactions

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Zhang, Y. [University of Rochester, NY (United States)] (ORCID:0000000310177953), Heuer, P. V. [University of Rochester, NY (United States)] (ORCID:0000000150506606), Wen, H. [University of Rochester, NY (United States)] (ORCID:000000018567380X), Davies, J. R. [University of Rochester, NY (United States)] (ORCID:0000000182338272), Ren, C. [University of Rochester, NY (United States)] (ORCID:0000000208584827), Schaeffer, D. B. [University of California-Los Angeles, CA (United States)] (ORCID:0000000316755910), Blackman, E. G. [University of Rochester, NY (United States)], Zhang, J. [University of Rochester, NY (United States)], Bret, A. [Universidad de Castilla-La Mancha, Ciudad Real (Spain); Campus Universitario de Ciudad Real (Spain)] (ORCID:0000000320300046), García-Rubio, F. [Pacific Fusion Corporation, Fremont, CA (United States)] (ORCID:0000000271683190). 2026-03-10. Collisionless ion-electron energy exchange in magnetized shocks. https://doi.org/10.1103/16zv-35kt

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