HR: 14:00h
AN: SH53B-02    [Abstracts]
TI: Solar wind structures associated with multiday Helium-3 rich periods of solar energetic particles
AU: * Kocharov, L
EM: kocharov@utu.fi
AF: Space Environment Center, 325 Broadway, Boulder, CO 80305,
AU: Laivola, J
EM: jaolla@utu.fi
AF: University of Turku, Departmet of Physics, Turku, 20014, Finland
AU: Mason, G M
EM: glenn.mason@jhuapl.edu
AF: Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723-6099,
AU: Didkovsky, L
EM: leonid@usc.edu
AF: University of Southern California, Space Sciences Center, Los Angeles, CA 90089-1341,
AU: Judge, D L
EM: judge@usc.edu
AF: University of Southern California, Space Sciences Center, Los Angeles, CA 90089-1341,
AB: Survey of helium isotope abundance data (1997--2005) measured with the Ultra–Low-Energy Isotope Spectrometer (ULEIS) on the Advanced Composition Explorer ( ACE) has revealed multiday periods of ³He-rich solar energetic particles (SEPs) in the energy range of ~0.4--10 MeV nucleon^-1 with ³He/⁴He~0.1--1. We analyze 17 periods, where there were good counting statistics, using also in situ measurements of solar wind at ACE and Solar and Heliospheric Observatory ( SOHO) along with solar observations by SOHO telescopes, to study coronal and interplanetary magnetic field structures associated with multiday periods of ³He-rich SEPs. Then we employ a simple model of corotating compression in solar wind to estimate possible effect of observed solar wind profiles on confinement of ³He- rich SEPs in interplanetary magnetic field structures, which indicates that the large-scale compressions in solar wind is one of significant factors contributing to occurrence of multiday periods of ³He-rich SEPs.
DE: 7509 Corona
DE: 7514 Energetic particles (2114)
DE: 7859 Transport processes
DE: 7959 Models
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting