In this paper, we will investigate the heating of the solar corona by the resonantabsorption of Alfven waves in a viscous and isothermal atmosphere permeated by a horizontalmagnetic field. It is shown that if the viscosity dominates the motion in a high (low)-βplasma,it creates an absorbing and reflecting layer and the heating process is acoustic (magnetoacoustic).When the magnetic field dominates the oscillatory process it creates a non-absorbing reflectinglayer. Consequently, the heating process is magnetohydrodynamic. An equation for resonance isderived. It shows that resonances may occur for many values of the frequency and of themagnetic field if the wavelength is matched with the strength of the magnetic field. At theresonance frequencies, magnetic and kinetic energies will increase to very large values which mayaccount for the heating process. When the motion is dominated by the combined effects of theviscosity and the magnetic field, the nature of the reflecting layer and the magnitude of thereflection coefficient depend on the relative strengths of the magnetic field and the viscosity.
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