Gravitational-wave-induced oscillations of a viscoelastic sphere
Siegel and Roth [Mon. Not. R. Astron. Soc. 408, 1742 (2010)] introduced an excitation model in which they treat a vibrating solar-like star due to external gravitational waves (GWs) as a gigantic spherical resonant mass detector. In this study, we complete their work by providing an expression for the damping term ηN that can be numerically evaluated. This allows us to numerically compute the Q-factor of the quadrupolar spheroidal modes and study its properties. We then provide an extension to the solid sphere model by presenting a formulation for a sphere composed of two layers of different material properties called the dual sphere. We are mainly interested on the Q-factors of the normal modes and examine how the parameters of the solid and dual sphere models affect them.