Paper#: 59
Poster #: 2
Session Name: Poster Session 1
Room: East Ballroom
Day: Tuesday
Time: 10:10 a.m.-Noon
Abstract Title: Average Behavior of the Solar Wind Parameters around Breakups
PresentSurname: Maltsev, Y.P.
All Authors: Y.P. Maltsev, A.A. Arykov, I. V. Golovchanskaya
Abstract : Temporal behavior of the solar wind parameters in the course of substorms has been analyzed by superimposed epoch technique. For 311 auroral breakups observed in January - June, 1997 by the optical system of the Polar satellite no pronounced variations in the averaged solar wind density and velocity inside the 8-hour range centered at the breakup onset were found. The averaged Bz IMF turned negative about 2 hours prior the breakups, without any prominent changes at the breakup onset. Furthermore, it appeared that southward IMF orientation is not a necessary condition for breakup initiation, as 71 events (23% of the total amount) occurred after hourly northward Bz IMF. Thus in spite of generally accepted solar wind control of substorms their onsets do not seem to need triggering by any sharp variations of the solar wind parameters.