HR: 14:30h
AN: SH53A-03    [Abstracts]
TI: MeV Ion Anisotropies in the Vicinity of Interplanetary Shocks
AU: * Richardson, I G
EM: ian.richardson@gsfc.nasa.gov
AF: Astroparticle Physics Laboratory, Code 661, NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: * Richardson, I G
EM: ian.richardson@gsfc.nasa.gov
AF: Department of Astronomy/CRESST, University of Maryland, College Park, MD 20742, United States
AU: Cane, H V
EM: hilary.cane@utas.edu.au
AF: Astroparticle Physics Laboratory, Code 661, NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Cane, H V
EM: hilary.cane@utas.edu.au
AF: School of Mathematics and Physics, University of Tasmania, Hobart, 7001, Australia
AU: von Rosenvinge, T T
EM: tycho@milkyway.gsfc.nasa.gov
AF: Astroparticle Physics Laboratory, Code 661, NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AB: The anticipated signatures of interplanetary shock acceleration to be found in energetic ion anisotropies in the vicinity of interplanetary shocks include near-isotropic particle distributions consistent with of diffusive shock acceleration, "pancake" distributions indicative of shock drift acceleration, and flow reversals suggestive of a particle acceleration region passing by the observing spacecraft. In practice, while clear examples of these phenomena exist, more typically, particle anisotropies near interplanetary shocks show considerable variation in time and space, both in individual events and from event to event. We investigate the properties of MeV/n ions in the vicinity of a number of interplanetary shocks associated with the largest energetic particle events of solar cycle 23, and previous cycles, including their intensity-time profiles, anisotropies, and relationship with local solar wind structures, using observations from the IMP 8, ISEE-3, Helios 1 and 3 spacecraft. The aim is to help to understand the role of shocks in major solar energetic particle events.
DE: 2111 Ejecta, driver gases, and magnetic clouds
DE: 2114 Energetic particles (7514)
DE: 2134 Interplanetary magnetic fields
DE: 2139 Interplanetary shocks
DE: 2164 Solar wind plasma
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Joint Assembly