High-frequency leaky standing sausage and kink mode waves in magnetic slab

The theoretical framework for analyzing wave and oscillatory behavior in the structured solar corona using slab geometry, where space is filled with uniform low-b plasma, is considered as one of the prominent models for a number of magnetic structures. Numerous observations from the initial findings of the Transition Region and Coronal Explorer satellite to the most recent ones are successfully explained by adopting this model. To formulate the oscillatory characteristics of magnetohydrodynamic (MHD) waves, most studies have the concept of trapped surface and body waves. In this study, we formulate the dispersion relation for leaky fast sausage and kink mode waves to investigate the wave period, damping time, Q-factor, and coronal magneto-seismological characteristics for the non-ideal MHD model by considering a parametric scan of the width and length of the loop. A key aspect of our approach is incorporating viscosity as a damping mechanism, which directly affects the imaginary part of the complex frequency, leading to comparatively more wave damping. In our study, we focus on how viscosity alters the characteristics of leaky fast sausage and kink MHD waves within the low-b regime. The behavior of leaky fast MHD waves is analyzed under the consideration of long (ka < 1) and short wavelength (ka > 1) approximation of the wave as: (i) For long wavelength limit, the periods of both fast leaky sausage and kink mode waves are influenced solely by the loop width and remain independent of the loop length. However, for the case of short wavelength limit, the period of sausage and kink modes depends on both the loop width and the loop length. (ii) Second, we have studied the impact of non-ideal term (i.e., viscosity) on the damping of these leaky fast MHD waves. The addition of viscosity in the ideal plasma model leads to stronger damping of fast leaky sausage and kink mode waves for both long and short wavelength limits.