HR: 10:55h
AN: SH12A-03 [Abstracts]
TI: Energetics of Electron and Ion Acceleration in RHESSI Flares
AU: * Shih, A Y
EM: ayshih@ssl.berkeley.edu
AF: Department of Physics and Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA
94720
United States
AU: Smith, D M
EM: dsmith@scipp.ucsc.edu
AF: Department of Physics and Santa Cruz Institute for Particle Physics, University of California, Santa
Cruz, Santa Cruz, CA 95064
United States
AU: Lin, R P
EM: rlin@ssl.berkeley.edu
AF: Department of Physics and Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA
94720
United States
AU: Share, G H
EM: gerald.share@nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375
United States
AU: Murphy, R J
EM: ronald.murphy@nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375
United States
AU: Schwartz, R A
EM: richard.schwartz@gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Greenbelt Road, Greenbelt, MD 20771
United States
AU: Tolbert, A K
EM: kim.tolbert@gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Greenbelt Road, Greenbelt, MD 20771
United States
AB:
The Reuven Ramaty High-Energy Solar Spectroscopic Imager ( RHESSI) has observed both high-energy electron
bremsstrahlung emission and nuclear gamma-ray line emission from solar flares. The gamma-ray lines are produced when
energetic ions interact with the ambient medium through various processes including neutron capture and nuclear
de-excitation. By comparing electron-related emission and ion-related emission in flares, one can put constraints on the
acceleration mechanism for electrons and ions. Of the gamma-ray lines, RHESSI is most sensitive to the neutron-capture
line at 2.223 MeV, which is indirectly produced by protons accelerated above 30 MeV. RHESSI has observed eleven
flares with significant neutron-capture line emission and can place upper limits on other flares. We compare the fluence in
this line with the electron bremsstrahlung fluence above 300 keV for all RHESSI flares that extend to such energies and
find strong evidence for a linear correlation between these two quantities. This correlation implies that the mechanism
that accelerates protons above 30 MeV is directly associated with the mechanism that accelerates electons above 300 keV. We
also look for correlations between these types of emission and soft X-ray emission as defined by GOES class. Finally,
we compare these flares with flares observed in the past by the Solar Maximum Mission ( SMM) satellite.
The work at the University of California, Berkeley, was supported by NASA contract NAS 5-98033.
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7554 X-rays, gamma rays, and neutrinos
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005