Fine Structures of an EUV Wave Event from Multi-Viewpoint Observations

TL;DR

This study analyzes a 2010 EUV wave event using multi-viewpoint SDO and STEREO data, revealing a fast coronal Moreton wave and a slower EIT wave, with insights into their nature and stationary fronts.

Contribution

It provides detailed multi-viewpoint observations distinguishing between a fast-mode wave and an apparent EIT wave, and explains stationary fronts as mode conversions.

Findings

Identified a fast coronal Moreton wave at ~445 km/s

Detected a slower EIT wave at ~298 km/s

Observed stationary fronts explained by mode conversion near streamers

Abstract

In this study, we investigate an extreme ultraviolet (EUV) wave event on 2010 February 11, which occurred as a limb event from the Earth viewpoint and a disk event from the STEREO--B viewpoint. We use the data obtained by the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO) in various EUV channels. The EUV wave event was launched by a partial prominence eruption. Similar to some EUV wave events in previous works, this EUV wave event contains a faster wave with a speed of $\sim$445$\pm$6 km s$^{-1}$, which we call coronal Moreton wave, and a slower wave with a speed of $\sim$298$\pm$5 km s$^{-1}$, which we call "EIT wave". The coronal Moreton wave is identified as a fast-mode wave and the "EIT wave" is identified as an apparent propagation due to successive field-line stretching. We also observe a stationary front associated with the fast mode EUV wave. This stationary front is explained as mode conversion from the coronal Moreton wave to a slow-mode wave near a streamer.