Local Stability and Structure of a Differentially Rotating Star of Non- Uniform Density
Keywords:
Roche-Equipotential, Equilibrium Structure, Tidal Distortion, Differential Rotation, Mass VariationAbstract
A method is proposed to compute the theoretical estimation of physical parameters and stability of differential
rotation for polytropic stars including mass variation. The law of differential rotation is assumed to be in the form4
3
2
21
2 )( sbsbbs
, the angular velocity of rotation (ω) is a function of distance (s) of the fluid element
from the axis of rotation. Utilizing the concepts of Roche- equipotential and averaging approach of (Kippenhahn
and Thomas, 1970) in a manner, earlier used by (Saini, et al., 2012) to incorporate the effects of differential
rotation on the equilibrium structure of polytropic stellar models. The inner structure of differentially rotating
polytropic models of a star is demonstrated by calculating various physical parameters for suitable combinations
of parameters
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References
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