SOLAR-WIND STREAMER BELT STRUCTURE

In the course of 2 days in October 1978, ISEE 3 encountered 14 magneti c field reversals, five pronounced and several lesser high-beta region s called ''plasma sheets,'' two distinct entropy regimes, two heat flu x dropouts (HFDs), and planar magnetic structure led by a shock wave. The complexity of the interval afforded an excellent opportunity to de termine the relationships between these streamer belt structures, thei r geometry and topology, and the resulting implications for the struct ure of the heliospheric current sheet (HCS). None of the results of th ree tests applied to the data support a wavy or folded HCS hypothesis. In particular, a test for true magnetic polarity using primarily heat flux data indicated that the field reversals occurred in a predominan tly toward sector with three pockets of true away polarity and three o f false away polarity. The results are consistent with a view in which current sheets bound intertwined flux ropes, some of which coil back on themselves, possibly as remnants of transient coronal activity. A c omparison between joint occurrences of the various structures showed t hat the most intense plasma sheets in the interval coincided with true polarity reversals, that nearly every reversal, whether true or false , corresponded to at least a weak plasma sheet, and that plasma sheets occurred within HFD intervals. The plasma sheet/HFD relationship was statistically confirmed in a search for plasma sheets in published HFD s.