Electron Bulk Acceleration and Thermalization at Earth's Quasiperpendicular Bow Shock.

Academic Article

Abstract

  • Electron heating at Earth's quasiperpendicular bow shock has been surmised to be due to the combined effects of a quasistatic electric potential and scattering through wave-particle interaction. Here we report the observation of electron distribution functions indicating a new electron heating process occurring at the leading edge of the shock front. Incident solar wind electrons are accelerated parallel to the magnetic field toward downstream, reaching an electron-ion relative drift speed exceeding the electron thermal speed. The bulk acceleration is associated with an electric field pulse embedded in a whistler-mode wave. The high electron-ion relative drift is relaxed primarily through a nonlinear current-driven instability. The relaxed distributions contain a beam traveling toward the shock as a remnant of the accelerated electrons. Similar distribution functions prevail throughout the shock transition layer, suggesting that the observed acceleration and thermalization is essential to the cross-shock electron heating.
  • Authors

  • Chen, L-J
  • Wang, S
  • Wilson, LB
  • Schwartz, S
  • Bessho, N
  • Moore, T
  • Gershman, D
  • Giles, B
  • Malaspina, D
  • Wilder, FD
  • Ergun, RE
  • Hesse, M
  • Lai, H
  • Russell, C
  • Strangeway, R
  • Torbert, Roy
  • F-Vinas, A
  • Burch, J
  • Lee, S
  • Pollock, C
  • Dorelli, J
  • Paterson, W
  • Ahmadi, N
  • Goodrich, K
  • Lavraud, B
  • Le Contel, O
  • Khotyaintsev, Yu V
  • Lindqvist, P-A
  • Boardsen, S
  • Wei, H
  • Le, A
  • Avanov, L
  • Status

    Publication Date

  • June 1, 2018
  • Has Subject Area

    Published In

    Digital Object Identifier (doi)

    Pubmed Id

  • 29906189
  • Start Page

  • 225101
  • Volume

  • 120
  • Issue

  • 22