ABSTRACT. MHD wave activity associated with a flare was observed in coronal active region AR 8270 in the extreme ultraviolet (EUV) by the Transition Region and Coronal Explorer (TRACE) satellite on 1998 July 14. In this study, a three-dimensional MHD model of the active region field was initialized using a National Solar Observatory (NSO) Kitt Peak magnetogram and potential extrapolation of the magnetic field, together with gravitationally stratified density. To model the observed wave activity following the flare, a velocity pulse was launched into a model active region from below. It was found that the global oscillations in the model active region are in good qualitative agreement with observations. The main difference between the observations and the model is in the oscillation of several individual loops that damp on longer timescales compared to the corresponding magnetic field line oscillation damping in the model.

Subject headings: MHD; Sun: corona; Sun: flares; Sun: magnetic fields; waves

Print publication: Issue 2 (2007 February 1)
Received 2006 May 12, accepted for publication 2006 October 6