title: Understanding the Physical Nature of Coronal "EIT Waves".
abstract: For almost 20 years the physical nature of globally propagating waves in the solar corona (commonly called "EIT waves") has been controversial and subject to debate. Additional theories have been proposed over the years to explain observations that did not agree with the originally proposed fast-mode wave interpretation. However, the incompatibility of observations made using theExtreme-ultraviolet Imaging Telescope(EIT) onboard theSolar and Heliospheric Observatorywith the fast-mode wave interpretation was challenged by differing viewpoints from the twinSolar Terrestrial Relations Observatoryspacecraft and data with higher spatial and temporal resolution from theSolar Dynamics Observatory. In this article, we reexamine the theories proposed to explain EIT waves to identify measurable properties and behaviours that can be compared to current and future observations. Most of us conclude that the so-called EIT waves are best described as fast-mode large-amplitude waves or shocks that are initially driven by the impulsive expansion of an erupting coronal mass ejection in the low corona.
authors.affiliation: Mullard Space Science Laboratory, UCL, Holmbury St. Mary, Dorking, Surrey RH5 6NT UK.
authors.forename: D M
authors.identifier: 0000-0003-3137-0277
authors.initials: DM
authors.lastname: Long
authors.affiliation: School of Physics, Trinity College Dublin, College Green, Dublin 2, Ireland.|Northumbria University, Newcastle upon Tyne, NE1 8ST UK.
authors.forename: D S
authors.identifier: 0000-0002-4183-9895
authors.initials: DS
authors.lastname: Bloomfield
authors.affiliation: School of Astronomy & Space Science, Nanjing University, 163 Xianlin Ave., Nanjing, 210023 P.R. China.
authors.forename: P F
authors.identifier: 0000-0002-7289-642X
authors.initials: PF
authors.lastname: Chen
authors.affiliation: Predictive Science Inc., 9990 Mesa Rim Rd., Suite 170, San Diego, CA 92121 USA.
authors.forename: C
authors.identifier: 0000-0003-1759-4354
authors.initials: C
authors.lastname: Downs
authors.affiliation: School of Physics, Trinity College Dublin, College Green, Dublin 2, Ireland.
authors.forename: P T
authors.identifier: 0000-0001-9745-0400
authors.initials: PT
authors.lastname: Gallagher
authors.affiliation: College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 USA.
authors.forename: R-Y
authors.identifier: 0000-0002-2106-9168
authors.initials: RY
authors.lastname: Kwon
authors.affiliation: Kanzelhöhe Observatory/IGAM, Institute of Physics, University of Graz, 8010 Graz, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Vanninathan
authors.affiliation: Kanzelhöhe Observatory/IGAM, Institute of Physics, University of Graz, 8010 Graz, Austria.
authors.forename: A M
authors.initials: AM
authors.lastname: Veronig
authors.affiliation: Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD 20723 USA.
authors.forename: A
authors.identifier: 0000-0002-8164-5948
authors.initials: A
authors.lastname: Vourlidas
authors.affiliation: Faculty of Geodesy, Hvar Observatory, Kaciceva 26, 10000 Zagreb, Croatia.
authors.forename: B
authors.identifier: 0000-0002-0248-4681
authors.initials: B
authors.lastname: Vršnak
authors.affiliation: Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Warmuth
authors.affiliation: Faculty of Geodesy, Hvar Observatory, Kaciceva 26, 10000 Zagreb, Croatia.
authors.forename: T
authors.initials: T
authors.lastname: Žic
keywords: Coronal mass ejections, low coronal signatures; Waves, magnetohydrodynamic; Waves, propagation; Waves, shock