Markus J. Aschwanden Submitted: 06-Aug-2002 17:19
Oscillations of coronal loops have been discovered with
TRACE and are now also found by SUMER. Dozens of events
are already known, most of the excited by a flare or a
destabilizing filament. The study of these oscillations
started a new field of "coronal seismology". One not
understood physical problem is the damping mechanism.
There are at least 5 different theories (non-linear effects,
footpoint leakage, lateral leakage, phase mixing, resonant
absorption of Alfven waves). With RHESSI we can for the
first time measure accurate density scale heights at the
chromospheric footpoints, which provide crucial constraints
for modeling damping mechanisms in terms of footpoint
leakage.
Participants: Markus J. Aschwanden, Bart DePontieu
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