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Propagation and Dissipation of Slow Magneto-Acoustic Waves in Coronal Loops

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Author Affiliations

  • 1Department of Physics, K G K College, Moradabad 244 001, Uttar Pradesh, INDIA
  • 2 Department of Physics, Hindu College, Moradabad 244 001, Uttar Pradesh, INDIA
  • 3 Dept. of Applied Sciences, Visveshwarya Institute of Engg. and Tech., Dadri, G. B. Nagar, UP, INDIA

Res. J. Recent Sci., Volume 1, Issue (2), Pages 34-41, February,2 (2012)

Abstract

We study the spatial damping of slow magnetoacoustic waves in homogeneous, isothermal, and unbounded coronal plasma permeated by a uniform magnetic field, with physical properties akin to those of coronal loops. Taking into account an energy equation with optically thin radiative losses, thermal conduction, and heating we obtain a fourth-order polynomial in the wavenumber k, which represents the dispersion relation for slow and thermal MHD waves. The fourth order dispersion relation has been solved numerically for different loop parameters. It is found that damping length of slow-mode waves exhibits varying behavior depending upon the physical parameters of the loop. We found that for solar coronal loops, the dominant wave damping mechanism is compressive viscosity and thermal conduction with less significant contribution by radiation. For any considered period, slow waves have much shorter damping length in hot coronal loops than that in cool loops and also slow waves damped very quickly in hot and long coronal loops.

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