WIND observations of the electron foreshock

R. J. Fitzenreiter, A. F. Viñas, A. J. Klimas, R. P. Lepping, M. L. Kaiser, and T. J. Onsager

NASA-Goddard Space Flight Center, Greenbelt, MD 20771

Abstract:

Observations in the electron foreshock by the WIND/SWE investigation are presented. Between November 30 - December 28, 1994, WIND made repeated back and forth crossings of the leading edge of the electron foreshock. We present observations during one five hour interval from this period. Foreshock crossings are readily identified in the SWE data by the onset of an enhanced flux of backstreaming electrons and by a reversal of the electron heat flux. The measured velocity distribution functions indicate that both magnetic reflection from the bow shock and upstream leakage through the shock are responsible for the backstreaming electrons measured upstream. Resolved bumps are frequently observed on reduced velocity distributions and are shown to be associated with an increased electric field intensity measured by the WIND/WAVES experiment.

Geophys. Res. Lett., 23, 1235-1238, 1996