Extreme-Ultraviolet Wave and Accompanying Loop Oscillations

Abstract

We present the observations of an extreme-ultraviolet (EUV) wave, which originated from the active region (AR) NOAA 12887 on 28 October 2021, and its impact on neighboring loops. The event was observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO) satellite at various wavebands and by the Solar TErrestrial RElations Observatory-Ahead (STEREO-A) with its Extreme-Ultraviolet Imager (EUVI) and COR1 instruments with a different view angle from SDO. We show that the EUV-wave event consists of several waves as well as nonwave phenomena. The wave components include: the fast-mode part of the EUV wave event, creation of oscillations in nearby loops, and the appearance of wave trains. The nonwave component consists of stationary fronts. We analyze selected oscillating loops and find that the periods of these oscillations range from 230 – 549 s. Further, we compute the density ratio inside and outside the loops and the magnetic-field strength. The computed density ratio and magnetic field are found to be in the ranges of 1.08 – 2.92 and 5.75 – 8.79 G, respectively. Finally, by combining SDO and STEREO-A observations, we find that the observed EUV-wave component propagates ahead of the CME leading edge.