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Investigating Alfvénic wave propagation in coronal open-field regions
R J Morton1, S Tomczyk2, R Pinto3
11] Department of Mathematics and Information Sciences, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK. [2] High Altitude Observatory, National Center for Atmospheric Research, Boulder, Colorado 80307-3000, USA.
Nature Communications
|July 28, 2015
Summary
Counter-propagating Alfvén waves, crucial for solar wind acceleration, have been observed in the Sun's corona. This discovery supports turbulence models for understanding solar and stellar wind acceleration.
Area of Science:
- * Astrophysics
- * Solar Physics
- * Plasma Physics
Background:
- * Solar and stellar winds are accelerated by physical mechanisms that remain a mystery.
- * Alfvén waves have been known to exist far from the Sun since the 1970s.
- * Recent observations confirm the presence of Alfvénic waves throughout the solar atmosphere.
Purpose of the Study:
- * To demonstrate the existence of counter-propagating Alfvénic waves in open coronal magnetic fields.
- * To provide observational insights into the generation, reflection, and propagation of these waves.
- * To support and constrain recent Alfvén wave turbulence models for solar wind acceleration.
Main Methods:
- * Observational analysis of Alfvénic waves in the solar corona.
- * Investigation of wave generation, reflection, and propagation mechanisms.
- * Correlation of findings with existing Alfvén wave turbulence models.
Main Results:
- * Demonstrated the existence of counter-propagating Alfvénic waves in open coronal magnetic fields.
- * Revealed key observational details regarding their generation and reflection in the upper atmosphere.
- * Tracked their outward propagation into the solar wind.
Conclusions:
- * Confirmed the presence of counter-propagating Alfvénic waves, a key component for turbulence development.
- * Enhanced understanding of Alfvénic wave propagation in the solar atmosphere.
- * Provided crucial observational support and constraints for Alfvén wave turbulence models of solar wind acceleration.
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