OBSERVED CORE OF A GRADUAL SOLAR ENERGETIC PARTICLE EVENT

Journal Article · Mon Dec 20 04:00:00 EST 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/725/2/2262· OSTI ID:21476645

Kocharov, L; Valtonen, E ^[1]; Reiner, M J; Thompson, B J ^[2]; Klassen, A ^[3]

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1. Space Research Laboratory, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland)
2. NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
3. Institut fuer Experimentelle und Angewandte Physik, Christian-Albrechts-Universitaet Kiel, D-24098 Kiel (Germany)

Using space-borne particle and EUV detection and radio spectrograms from both ground-based and space-borne instruments, we study the first phase of the major solar energetic particle (SEP) event associated with the western solar flare and fast and wide coronal mass ejection (CME) on 2000 April 4. The SEP event being observed at the magnetic connection to the eruption's center starts with deka-MeV nucl{sup -1} helium- and relativistic electron-rich production from coronal sources identified with the electromagnetic diagnostics and the SEP event modeling. The broadband observations and modeling of the initial phase of the 'well-connected' major SEP event support the idea that acceleration of SEPs starts in the helium-rich plasma of the eruption's core in association with coronal shocks and magnetic reconnections caused by the CME liftoff, and that the coronal component dominates during the first hour of the SEP event considered, not yet being shielded by the CME bow shock in the solar wind. The first phase of the SEP event is followed by a second phase of SEP production associated with a decelerating CME-driven shock wave in the solar wind, which accelerates ions from a distinct, helium-poor seed particle population that may originate from the CME interaction with a coronal streamer.

• OSTI ID: 21476645
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 725; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
ENERGY RANGE
ERUPTION
FERMIONS
FLUIDS
GASES
HELIUM
LEPTONS
MAIN SEQUENCE STARS
NONMETALS
PLASMA
RARE GASES
RELATIVISTIC RANGE
SHOCK WAVES
SIMULATION
SOLAR ACTIVITY
SOLAR FLARES
SOLAR WIND
STARS
STELLAR ACTIVITY
STELLAR FLARES
STELLAR WINDS
SUN