HR: 08:15h
AN: SH11B-02    [PDF]
TI: Interplanetary Coronal Mass Ejections Observed at Earth and Voyager 2
AU: * Wang, C
EM: cw@space.mit.edu
AF: Lab. for Space Weather Chinese Academy of Sciences, P.O. Box 8701, Bejing, 100080 China
AU: * Wang, C
EM: cw@space.mit.edu
AF: MIT Center for Space Research, 77 Mass. Ave., Cambridge, MA 02139 United States
AU: Richardson, J D
EM: jdr@space.mit.edu
AF: MIT Center for Space Research, 77 Mass. Ave., Cambridge, MA 02139 United States
AB: While spacecraft such as ACE, IMP8, Wind are monitoring the solar wind near Earth, Voyager 2 continues to explore the outer heliosphere. The ability to match solar wind features at widely separated points in the heliosphere provides us detailed information on the evolution of the solar wind. In this study, we present a survey of interplanetary coronal mass ejections (ICMEs) observed during time periods when Earth and Voyager 2 are within about 60 degrees in longitude from 1998 to present. We try to track the evolution of the ejecta from the inner to outer heliosphere by using a numerical model. Preliminary results show that boundaries of the ejecta region are difficult to determine as the structure undergoes significant evolution and interacts with other solar wind structures. Many ICMEs found at Earth did not have obvious counterparts at Voyager 2. For some cases, however, we are able to identify the heliospheric remnants of the ICMEs in the Voyager observations based on numerical results and, when available and relevant, helium abundances. These events are invaluable for the study of the dynamical processes of ICMEs in the heliosphere. Our numerical results demonstrate that, in general, ICMEs expanding to 2$\sim$5 times of their original widths near Earth within a distance of $\sim$30 AU, then maintain a roughly constant width outside this distance.
DE: 2111 Ejecta, driver gases, and magnetic clouds
DE: 2164 Solar wind plasma
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting