On the role of hydrodynamic waves in the corona and the base of the solar wind.
Abstract
Hydromagnetic waves are of interest for heating the corona or coronal loops and for accelerating the solar wind. This paper enumerates some of the limitations that must be considered before hydromagnetic waves are taken seriously. In the lowest part of the corona, waves interact so that a significant fraction of the coronal wave flux should have periods as ≈10 s. If the problem of interest determines either a flux of wave energy or a dissipation rate, the distance that each wave mode can travel can be specified, and for at least one mode it must be consistent with the size and location of the region where the waves are to act. Heating of coronal loops observed by X-rays can be explained if the strength of the magnetic field along the loop lies within a rather narrow range and if the wave period is sufficiently short. In general, Alfvén waves travel furthest and reach high into the corona and into the solar wind. The radial variation of the magnetic field is the most important parameter determining where the waves are dissipated. Heating of coronal helmets by Alfvén waves is probable.
- Publication:
-
Solar Physics
- Pub Date:
- April 1977
- DOI:
- 10.1007/BF00935799
- Bibcode:
- 1977SoPh...52..163W
- Keywords:
-
- Magnetohydrodynamic Waves;
- Solar Corona;
- Solar Wind;
- Chromosphere;
- Collisional Plasmas;
- Energy Dissipation;
- Magnetic Effects;
- Solar Heating;
- Solar Magnetic Field;
- Wave Attenuation;
- Wave Interaction;
- Solar Physics;
- Magnetic Field;
- Solar Wind;
- Narrow Range;
- Dissipation Rate;
- Wave Energy;
- Hydromagnetic Waves:Solar Corona;
- Hydromagnetic Waves:Solar Wind;
- Solar Corona:Heating;
- Solar Wind: Heating