Isolating Cme Signals In Coronagraph Images

A technique has been developed to separate the signal of CMEs from the background quiescent corona. The method works best for a radial corona (SECCHI/COR 2 or LASCO/C2 & C3 for example), but can be adapted to cope with non-radial coronal structure (SECCHI/COR 1 or MLSO coronameters). A brief summary of the technique will be given, followed by an overview of results, a discussion of limitations, and the implications for both CME and quiescent coronal science. The high temporal cadence of observations by the SECCHI instruments allow the viewing of dynamic events from the low corona (EUVI regions) to the extended corona. For the first time, even fairly small events can be tracked as they propogate and evolve through the corona. The CME separation technique provides a very useful tool to view this evolution, particularly in the white light coronagraph images where faint CME signals cannot be effectively viewed in regions containing bright streamers.