Catholic University of America and NASA Goddard Space Flight Center

 
Title : Global fast-mode waves observed by STEREO SECCHI COR1, associated with coronal EIT/EUV waves

 

Catholic University of America and NASA Goddard Space Flight Center Coronal "extreme ultraviolet (EUV) waves" are globally propagating large-scale bright fronts, across the solar disk in EUV passbands. There has been much debate on the physical nature of EUV waves ever since their first discovery in 1996, whether they are real fast-mode waves or not. Here we report observations of real fast-mode waves propagating across the solar radial background magnetic fields, not only in the low solar corona as a form of EUV waves, but also in the high solar corona (above 1.5 R⊙) as a form of propagating radial density enhancements. The average speeds of the wave are 540, 883, 1175, 1576, and 2027 km s−1 at 1.0, 1.5, 2.0, 2.5, and 3.0 R⊙, respectively. In addition, the origin of enigmatic stationary fronts of EUV waves can be explained by the kink mode oscillations along coronal streamers, triggered by the transit of fast-mode waves.