MHD waves in coronal arcades.
Abstract
The MHD wave behavior in the solar corona with magnetic field having the shape of arcades is investigated. It is shown that a particular analytical solution to the linearized MHD equations can be obtained for perturbations with short wavelengths in the direction of the arcade tunnel. Two possibilities are considered regarding the related wave frequency: the high frequency domain yields MHD waves propagating along the tunnel of the arcade as a fast MHD mode while the low frequencies produce two decoupled wave modes representing the Alfvén and the slow magnetoacoustic wave, both modified by the gravity and the profile of the magnetic field. All these wave are stable, contrary to the case when the magnetic field is purely horizontal and when the magnetic buoyancy instabilities can set in.
- Publication:
-
Publications de l'Observatoire Astronomique de Beograd
- Pub Date:
- July 1995
- Bibcode:
- 1995POBeo..49..109C
- Keywords:
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- Solar Corona: Magnetohydrodynamics;
- Solar Corona: Magnetic Fields