Alexander Warmuth Submitted: 17-Aug-2005 02:08
Large-amplitude disturbances of the ambient corona are observed as coronal waves in imaging data and as type II radio bursts in dynamic radiospectra. There are indications that both coronal waves and metric (i.e. coronal) type II bursts are generated by the same perturbation, which seems to be a fast-mode MHD shock.
There has been a long debate on the causes of these disturbances, which can be summarized as "flare-generated blast wave vs. CME-drive bow shock". In order to constrain the cause of the coronal disturbances, we are measuring the kinematics of coronal waves (using a variety of spectral bands) and associated metric type II bursts. A back-extrapolation then yields the launch time as well as the starting point of the perturbation. This is then compared to the properties of the associated flare using RHESSI data. In particular, the evolution of the spectral shape and the total energy input during the launch phase should provide clues on whether coronal waves and shocks can be attributed to a flare-launched blast wave.
Participants: Alexander Warmuth, Gottfried Mann, Henry Aurass
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