عنوان مجله
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MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
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چکیده
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There are observational evidences for the existence of twisted magnetic field in the solar
corona. Here, we have investigated resonant damping of the magnetohydrodynamic (MHD)
kink waves in magnetic flux tubes. A realistic model of the tube with continuous magnetic
twist and radially inhomogeneous density profile has been considered. We have obtained the
dispersion relation of the kink wave using the solution to the linear MHD equations outside
the density inhomogeneity and the appropriate connection formula to the solutions across the
thin transitional boundary layer. The dependence of the oscillation frequency and damping
rate of the waves on the twist parameter and longitudinal wavenumber has been investigated.
For the flux tube parameters considered in this paper, we obtain rapid damping of the kink
waves comparable to the observations. In order to justify this rapid damping, depending on
the sign of the azimuthal kink mode number, m = +1 or −1, the background magnetic field
must have left- or right-handed twisted profile, respectively. For the model considered here,
the resonant absorption occurs only when the twist parameter is in a range specified by the
density contrast.
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