Radial oscillations of differentially rotating stellar models: Effect of mass variation

Abstract

A method is proposed to compute eigen-frequencies of small adiabatic pseudo-radial modes of oscillations of differentially rotating stellar models by taking into account the effect of mass variation on its equipotential surfaces inside the star. The developed approach has been used to compute certain radial modes of oscillations of polytropic stellar models having polytropic indices 1.5 and 3.0. The results obtained have been compared with results obtained earlier (\textit{for instance see – A. K. Lal, C. Mohan and V. P. Singh (2001), "Eigen-frequencies of small adiabatic barotropic modes of oscillations of differentially rotating polytropic star in binary systems", Indian Journal of Pure and Applied Mathematics, Vol. 32(12), 1765-1776}), without taking into account the mass variation. Certain conclusions based on this study have been drawn.