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Understanding the Physical Nature of Coronal "EIT Waves"
D M Long1, D S Bloomfield2,3, P F Chen4
1Mullard Space Science Laboratory, UCL, Holmbury St. Mary, Dorking, Surrey RH5 6NT UK.
Solar Physics
|December 31, 2016
Summary
The physical nature of solar corona EIT waves has been debated for 20 years. Most researchers now conclude these waves are fast-mode shocks driven by coronal mass ejections.
Area of Science:
- Solar Physics
- Plasma Astrophysics
- Heliophysics
Background:
- The nature of globally propagating waves in the solar corona, known as EIT waves, has been debated for nearly two decades.
- Previous observations and proposed theories have led to conflicting interpretations regarding their physical mechanisms.
Purpose of the Study:
- To reexamine existing theories explaining EIT waves.
- To identify measurable properties and behaviors for comparison with observational data.
Main Methods:
- Review and analysis of observational data from various solar missions (EIT, STEREO, SDO).
- Comparison of theoretical models with high-resolution spatial and temporal data.
Main Results:
- Inconsistencies in earlier interpretations were highlighted by data from STEREO and SDO.
- The study consolidates evidence supporting a particular wave interpretation.
Conclusions:
- The majority consensus is that EIT waves are best described as fast-mode large-amplitude waves or shocks.
- These waves are initiated by the impulsive expansion of erupting coronal mass ejections in the lower solar corona.
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