Effect of Electrical Resistivity on the Damping of Slow Sausage Modes

Recent observations of slow surface sausage modes in a photospheric magnetic pore have been shown to be heavily damped. Numerical calculations have shown that electrical resistivity plays a significant role in this damping process. The aim of the present paper is to make an independent analytical derivation that would confirm the importance of electrical resistivity in the damping of these modes. An analytical dispersion relation in the framework of resistive magnetohydrodynamics is derived for sausage modes in a straight cylinder with a circular cross section and a discontinuous boundary. The effect of electrical resistivity on the damping of slow sausage modes in photospheric pore conditions is then studied, by solving the obtained dispersion relation numerically. The obtained results agree with those from the numerical calculations.