Large-scale Globally Propagating Coronal Waves

Abstract

Large-scale, globally propagating wave-like disturbances have been observed in the solar chromosphere and by inference in the corona since the 1960s. However, detailed analysis of these phenomena has only been conducted since the late 1990s. This was prompted by the availability of high-cadence coronal imaging data from numerous spaced-based instruments, which routinely show spectacular globally propagating bright fronts. Coronal waves, as these perturbations are usually referred to, have now been observed in a wide range of spectral channels, yielding a wealth of information. Many findings have supported the "classical" interpretation of the disturbances: fast-mode MHD waves or shocks that are propagating in the solar corona. However, observations that seemed inconsistent with this picture have stimulated the development of alternative models in which "pseudo waves" are generated by magnetic reconfiguration in the framework of an expanding coronal mass ejection. This has resulted in a vigorous debate on the physical nature of these disturbances. This review focuses on demonstrating how the numerous observational findings of the last one and a half decades can be used to constrain our models of large-scale coronal waves, and how a coherent physical understanding of these disturbances is finally emerging. Article RevisionsLiving Reviews supports two ways of keeping its articles up-to-date:Fast-track revision. A fast-track revision provides the author with the opportunity to add short notices of current research results, trends and developments, or important publications to the article. A fast-track revision is refereed by the responsible subject editor. If an article has undergone a fast-track revision, a summary of changes will be listed here.Major update. A major update will include substantial changes and additions and is subject to full external refereeing. It is published with a new publication number.For detailed documentation of an article's evolution, please refer to the history document of the article's online version at http://dx

A Statistical Analysis of the Solar Phenomena Associated with Global EUV Waves

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“…a brightening resulting from the restructuring of the coronal magnetic field during the eruption of a coronal mass ejection). Note that a more detailed overview of the different theories proposed to explain the "EIT wave" phenomenon may be found in the recent reviews by Liu and Ofman (2014) and Warmuth (2015). However, the advent of high-cadence observations with the launch of the Solar Terrestrial Relations Observatory (STEREO; Kaiser et al, 2008) and Solar Dynamics Observatory (SDO; Pesnell, Thompson, and Chamberlin, 2012) spacecraft has begun to refine our understanding of this phenomenon.…”

Modelling Quasi-Periodic Pulsations in Solar and Stellar Flares

“…These are bright, wave-like (pulse) features propagating globally across the solar disk through the corona (Moses et al 1997;Thompson et al 1998). After being observed by different instruments, EIT waves later became known as large-scale Coronal Bright Fronts (CBFs, see reviews by Warmuth 2015) and also as Global Coronal Waves (Hudson 1999;.…”

Deriving the Properties of Coronal Pressure Fronts in 3d: Application to the 2012 May 17 Ground Level Enhancement

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