Interplanetary CMEs Without Observed Coronagraph CMEs
AIR FORCE RESEARCH LAB HANSCOM AFB MA
Pagination or Media Count:
The SMEI has observed 88 interplanetary coronal mass ejections ICMEs in 2003. This work has established that most of those ICMEs, observed beyond 30 degrees elongation angles, are associated with bright CMEs with appropriate speeds and position angles observed out to 30 R0solar in the SOHO LASCO coronagraph. However, about one quarter of the ICMEs do not have obvious candidate CME associations despite good LASCO observational coverage. We examine the characteristics of those SMEI ICMEs without LASCO CME associations to determine whether or how they differ from the other ICMEs. In particular we examine the speed profiles and brightness of those ICMEs. We discuss possible ways in which the ICMEs can arise as discrete observable structures in the interplanetary medium without being observed to any significant degree in coronagraph images.