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arXiv · 1111.5202

SDO/AIA Observations of Secondary Waves Generated by Interaction of the 2011 June 7 Global EUV Wave With Solar Coronal Structures

Ting Li·Jun Zhang·Shuhong Yang·Wei Liu
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Abstract

We present SDO/AIA observations of the interaction of a global EUV wave on 2011 June 7 with active regions (ARs), coronal holes (CHs) and coronal bright structures. The primary global wave has a three-dimensional dome shape, with propagation speeds ranging from 430-780 km/s in different directions. The primary coronal wave runs in front of the expanding loops involved in the CME and its propagation speeds are approximately constant within 10-20 minutes. Upon arrival at an AR on its path, the primary EUV wave apparently disappears and a secondary wave rapidly reemerges 75 Mm within the AR boundary at a similar speed. When the EUV wave encounters a coronal bright structure, an additional wave front appears there and propagates in front of it at a velocity nearly a factor of 2 faster. Reflected waves from a polar CH and a coronal bright structure are observed and propagate fractionally slower than the primary waves. Some of these phenomena can be equally explained by either a wave or non-wave model alone. However, taken together, these observations provide new evidence for the multitudes of global EUV waves, in which a true MHD fast-mode wave or shock propagates in front of an expanding CME bubble.

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Ting Li, Jun Zhang, Shuhong Yang, Wei Liu. 2011-11-22. SDO/AIA Observations of Secondary Waves Generated by Interaction of the 2011 June 7 Global EUV Wave With Solar Coronal Structures. https://doi.org/10.1088/0004-637x/746/1/13

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