THEORETICAL ESTIMATION OF STRUCTURES: DIFFERENTIALLY ROTATING STELLAR MODELS OF NON-UNIFORM MASSES

A method is proposed to compute equilibrium structures of differentially rotating polytropic stars. The law of differential rotation is assumed to be the form of 4 3 2 1 2 2  (s)  b  b s  b s .The angular velocity of rotation (ω) is a function of distance (s) of a fluid element from the axis of rotation.Kippenhahn and Thomas'saveraging approach and concepts of Roche-equipotential areutilised to incorporate the effects of differential rotation on the equilibrium structures of differentially rotating polytropic stellar models having non-uniform masses. The proposed mathematical modelling can be used to determine structures, oscillations and other distortions of premain sequence, main sequence and giant stars. KEYWORDS: Polytropes, Roche-equipotential