HR: 1340h
AN: SH13A-1129 [Abstracts]
TI: Solar X-rays and Energetic Electrons Escaping from the Sun
AU: * Krucker, s
EM: krucker@ssl.berkeley.edu
AF: Space Sciences Lab
UC Berkeley, 7 Gauss way, Berkeley, CA 94720-7450
United States
AU: Kontar, E P
EM: eduard@astro.gla.ac.uk
AF: University of Glasgow, The Kelvin Building, Glasgow, G12Q88
United Kingdom
AU: Lin, R P
EM: rlin@ssl.berkeley.edu
AF: Space Sciences Lab
UC Berkeley, 7 Gauss way, Berkeley, CA 94720-7450
United States
AB:
The Sun frequently accelerates electrons in solar flares and type
III radio bursts. Some of the accelerated electrons lose their energy
by collisions in the denser, lower solar atmosphere producing hard
X-ray (HXR) emissions and heat the corona, while others escape into
interplanetary space. Whether the HXR producing and the escaping
electrons are accelerated by the same mechanism is not known. Combining
RHESSI X-ray observations with in-situ observations of energetic
electrons from the WIND spacecraft allows for the first time a
detailed temporal, spatial, and spectral study.
Statistical results of 16 events with a close temporal agreement
between the HXR and the in-situ detected electrons (taking the time
of flight of the escaping electrons into account) show a correlation
between the HXR photon spectral index and the electron spectral index
observed in-situ thus indicating a common acceleration mechanism. Furthermore,
the solar X-ray source structure of these events look similar showing
hot loops with HXR footpoints plus an additional HXR source separated
from the loop by typically ~15". This source structure can be explained
by a simple magnetic reconnection model with newly emerging flux tubes that
reconnect with previously open field lines, so-called interchange
reconnection. Events with a delayed timing between the HXRs and the solar
release of escaping electrons (Krucker et al. 1999, Haggerty & Roelof 2002)
are presently investigated. If these delayed events are indeed
accelerated later in the event by shocks, no correlation between the
HXR photon spectrum and the in-situ observed electron spectrum is
expect to be found.
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7554 X rays, gamma rays, and neutrinos
DE: 2114 Energetic particles, heliospheric (7514)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting