High-Cadence Observations of a Global Coronal Wave by STEREO EUVI

Abstract

We report a large-scale coronal wave (so-called EIT wave) observed with high cadence by EUVI on board STEREO in association with the GOES B9.5 flare and double CME event on 2007 May 19. The EUVI instruments provide us with the unprecedented opportunity to study the dynamics of flare/CME associated coronal waves. The coronal wave under study reveals deceleration, indicative of a freely propagating MHD wave. Complementary analysis of the associated flare and erupting filament/CME hint at wave initiation by the CME expanding flanks, which drive the wave only over a limited distance. The associated flare is very weak and occurs too late to account for the wave initiation. © 2008, The American Astronomical Society, All rights reserved.