De‐2 photoelectron measurements consistent with a large scale parallel electric field over the polar cap

Winningham and Heikkila (1974) presented observations of “anomalous” photoelectron angular distributions over the polar caps. They interpreted these observations to be indicative of a large scale, outwardly directed, parallel electric field over the polar cap. The parallel field was observed to be spatially and/or temporally variable. New results from DE confirm and elaborate on these results. Some of the problems of data from a spinning spacecraft and low temporal/spatial resolution are alleviated. We reach the same conclusion concerning the possible existance of a large‐scale, low‐voltage parallel field and suggest causes for this field.