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

TL;DR

This study uses SDO/AIA data to analyze how a large-scale EUV wave interacts with solar structures, revealing multiple wave phenomena and supporting the interpretation of these waves as true MHD fast-mode waves or shocks.

Contribution

It provides detailed observations of secondary waves generated by interactions of a global EUV wave with various solar structures, supporting the wave nature of these phenomena.

Findings

Secondary waves reemerge within active regions after primary wave passage

Additional wave fronts appear at bright structures, moving faster than primary waves

Reflected waves from coronal holes and bright structures are observed

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.