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The Korean Astronomical Society (한국천문학회)
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MHD WAVES IN A STRATIFIED VISCOUS SOLAR ATMOSPHERE

  • KUMAR, NAGENDRA (Department of Mathematics, M. M. H. College,) ;
  • KUMAR, ANIL (Department of Mathematics, Maharaja Agrasen Institute of Technology) ;
  • MURAWSKI, K. (Group of Astrophysics, Institute of Physics, UMCS)
  • Received : 2014.11.30
  • Accepted : 2015.06.30
  • Published : 2015.09.30
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Abstract

We study MHD wave propagation in a gravitationally stratified isothermal viscous atmosphere of the Sun, permeated by a uniform magentic field. We perform numerical simulations by launching a slow wave on the upper boundary. The driven slow wave propagates down from low-${\beta}$ to high-${\beta}$ plasma across the region where the plasma ${\beta}$ is unity. It is found that mode conversion takes place at $z{\approx}-1.8$ in the layer ${\beta}{\approx}1$. The amplitudes of horizontal and vertical velocites are smaller than those obtained in the absence of viscosity.

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References

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