Document Type : Original Article
Author
Faculty of Physics, University of Tabriz, Tabriz, Iran
Abstract
The photospheric 5 min oscillations of the Sun can convert to Alfven waves by some conditions such as considering of a region and of a damping mechanism. Actually, 5 min oscillations appear in the photosphere and it does not seem to be able to pierce into the solar upper atmosphere because of the acoustic cut off of stratified medium and the sharp temperature gradient in the transition region. By perturbing the equilibrium state of the magnetized plasma, we showed that the acoustic and Alfven waves can interact through the nonlinear terms of the ideal MHD equations. We found that Alfven waves with twice the period of acoustic waves can propagate into upper layers when the speeds of sound and Alfven waves are equal. This condition obtain when ϖ=1/2ϖ .
Keywords
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