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  • Letter
  • Open Access

Electron heat flux and whistler instability in the Earth's magnetosheath

Ida Svenningsson1,2,3,*, Emiliya Yordanova1, Yuri V. Khotyaintsev1,2, Mats André1, Giulia Cozzani4, Alexandros Chasapis5, and Steven J. Schwartz5,6

  • *Contact author: ida.svenningsson@chalmers.se
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Phys. Rev. E 113, L063201 – Published 15 June, 2026

DOI: https://doi.org/10.1103/hd9q-t7z8

Abstract

Despite heat flux's role in regulating energy conversion in collisionless plasmas, its properties and evolution in the magnetosheath downstream of the Earth's bow shock are scarcely explored. We use Magnetospheric Multiscale in situ measurements to quantify and characterize the electron heat flux in the magnetosheath. We find that the heat flux is shaped by the magnetosheath magnetic field as it drapes around the magnetosphere. While it is affected by solar wind upstream conditions and increases with magnetic field strength, it is not substantially changed by local magnetosheath processes. Also, the heat flux is limited by whistler instability thresholds.

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Phys. Rev. E 113, L063201– Published 15 June, 2026
  • Received 27 October 2025
  • Accepted 21 May 2026
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