HR: 08:00h
AN: SH21A-01 INVITED     [PDF]
TI: The Acceleration of Coronal Mass Ejections
AU: * Burkepile, J T
EM: iguana@ucar.edu
AF: National Center for Atmospheric Research / HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: Hundhausen, A J
AF: National Center for Atmospheric Research / HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: MacQueen, R M
EM: rmac@ucar.edu
AF: National Center for Atmospheric Research / HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: DeToma, G
EM: detoma@ucar.edu
AF: National Center for Atmospheric Research / HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: Darnell, J A
EM: tdarnell@ucar.edu
AF: National Center for Atmospheric Research / HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: Gilbert, H R
EM: iggy@ucar.edu
AF: National Center for Atmospheric Research / HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AB: To determine quantitative estimates of the net force acting on a CME requires knowledge of the CME acceleration as a function of distance from the solar surface. The CME acceleration is determined directly from the observed time-height trajectory of the event by two methods: (a) sucessive differentials and (b) the use of polynomial and exponential function curve fitting to the trajectory, followed by successive derivatives. We examine the acceleration of a set of Coronal Mass Ejections (CMEs) observed over a wide range of coronal scale heights by combining observations of the low corona from the Mauna Loa Solar Observatory and the Extreme ultraviolet Imaging Telescope (EIT) on the Solar and Heliospheric Observatory (SOHO) spacecraft with observations from the LASCO coronagraphs onboard SOHO. We apply both of the above techniques to the events and conclude that CME acceleration is greatest in the low corona despite the strong force of gravity in that region. (In addition, CME start times determined from outer coronal (LASCO) observations alone tend to be systematically later than the actual start times, most likely due to the fact that LASCO observations cannot observe CME acceleration in the low corona.)
DE: 7509 Corona
DE: 7513 Coronal mass ejections
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting