Coronal Shock Waves, EUV Waves, and Their Relation to CMEs. III. Shock-Associated CME/EUV Wave in an Event with a Two-Component EUV Transient

摘要

On 17 January 2010, STEREO-B observed in extreme ultraviolet (EUV) and whitelight a large-scale dome-shaped expanding coronal transient with perfectlyconnected off-limb and on-disk signatures. Veronig et al. (2010, ApJL 716, 57)concluded that the dome was formed by a weak shock wave. We have revealed twoEUV components, one of which corresponded to this transient. All of itsproperties found from EUV, white light, and a metric type II burst matchexpectations for a freely expanding coronal shock wave including correspondenceto the fast-mode speed distribution, while the transient sweeping over thesolar surface had a speed typical of EUV waves. The shock wave was presumablyexcited by an abrupt filament eruption. Both a weak shock approximation and apower-law fit match kinematics of the transient near the Sun. Moreover, thepower-law fit matches expansion of the CME leading edge up to 24 solar radii.The second, quasi-stationary EUV component near the dimming was presumablyassociated with a stretched CME structure; no indications of opening magneticfields have been detected far from the eruption region.