HR: 1330h
AN: SH13B-02 [Abstracts]
TI: Modeling Wave Activity in Coronal Active Regions
AU: * Ofman, L
EM: leon.ofman@gsfc.nasa.gov
AF: Catholic University of America, NASA GSFC
Code 612.1, Greenbelt, MD 20771 United States
AB:
Wave activity in coronal active regions has been detected recently in EUV and as Doppler velocity oscillations by SOHO, and
in EUV by TRACE. The properties of the waves are determined by the excitation mechanism, and by the local physical
conditions, such as magnetic field strength and geometry, temperature, and density. It has been demonstrated that the phase
speeds of the various wave modes can be determined from observations. Using 3D MHD model I investigate the generation,
propagation, and damping of MHD waves in active regions, with the goal of developing a diagnostic tool of active region
physical properties. Photospheric magnetograms were used as the boundary conditions for the magnetic field model, and the
initial state was constructed using force-free extrapolation, and gravitationally stratified density. Here I expand previous
studies, and investigate possible excitation mechanism, as well as the damping of the transverse oscillations due to
resistivity, and leakage. I also investigate the generation, propagation, and damping of longitudinal oscillations in the
active region loops. In the present study improved boundary and initial conditions are developed, and the effects of
chromospheric coupling on the excitation and damping of the waves are investigated.
DE: 7509 Corona
DE: 7524 Magnetic fields
DE: 7827 Kinetic and MHD theory
DE: 7843 Numerical simulation studies
DE: 7871 Waves and instabilities
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly