Properties of Coronal Hole/Streamer Boundaries and Adjacent Regions as Observed by SPARTAN 201
Guhathakurta, M.; Strachan, L.; Kohl, J. L.; Gardner, L. D.; Smith, P. L.; Miralles, M. P.; Fisher, R. R.
United States
Abstract
The Spartan 201 flights from 1993 to 1995 provided us with observations in H I Lyman-α of several coronal hole/streamer boundaries and adjacent streamers during the declining phase of the current solar cycle: Analysis of the latitudinal dependence of the line intensities clearly shows that there is a boundary region at the coronal hole/streamer interface where the H I Lyman-α intensity reaches a minimum value. Similar results are also found in UVCS/SOHO observations. We also discuss differences in the coronal hole/streamer boundaries for different types of streamers and their changes over the three year period of Spartan 201 observations.