The Role of CMEs and Interplanetary Shocks in IMF Winding Angle Statistics

C. W. Smith and J. L. Phillips

Proceedings of Solar Wind 8, in press (1996)

Abstract:

We examine the possible role of CMEs and interplanetary shocks in past analyses of the large-scale winding of the IMF by extracting CME and shock observations from the ISEE-3 dataset and analyzing periods of the disturbed and undisturbed solar wind separately. We use the full ISEE-3 dataset representing the entire L1 mission (1978 -- 1982). We conclude that CMEs, the shocks upstream of CMEs and other interplanetary shocks are responsible for the apparent overwinding of the IMF spiral relative to the Parker prediction. The IMF winding angle asymmetry appears to be preserved after the removal of the interplanetary disturbances.