Non-radial oscillations of gaseous masses

Abstract

In this paper the fundamental frequencies of non-radial oscillations of polytropic gas spheres, belonging to spherical harmonics of orders l = 1 and 2, are evaluated, in a "second approximation", by a variational method. Also, the value of the ratio of the specific heats γ is determined for which an accidental degeneracy occurs between the fundamental modes of radial oscillation and non-radial oscillation belonging to l = 2; it is found that this value of γ varies from 16 for a homogeneous compressible sphere to 1 5719 for a poly trope of index n = 3.