Bidirectional solar wind electron heat flux events

ISEE 3 plasma and magnetic field data are used here to document the general characteristics of bidirectional electron heat flux events (BEHFEs). Significant field rotations often occur at the beginning and/or end of such events and, at times, the large-field rotations characteristic of 'magnetic clouds' are present. Approximately half of all BEHFEs are associated with and follow interplanetary shocks, while the other events have no obvious shock associations. When shock-associated, the delay from shock passage typically is about 13 hours, corresponding to a radial separation of about 0.16 AU. When independent of any shock association, BEHFEs typically are about 0.13 AU thick in the radial direction. It is suggested that BEHFEs are one of the more prominent signatures of coronal mass ejection events in the solar wind at 1 AU.