Local Stability and Structure of a Differentially Rotating Star of Non-Uniform Density

  • Kamal Krishan Singh Department of Mathematics, Graphic Era Deemed to be University, Dehradun, Uttarakhand
  • Seema Saini Department of Mathematics, Graphic Era Deemed to be University, Dehradun, Uttarakhand
  • Sunil Kumar Department of Mathematics, Himalayan School of Engineering and Technology, Swami Rama Himalayan University, Dehradun, Uttarakhand
Keywords: Roche-Equipotential, Equilibrium Structure, Tidal Distortion, Differential Rotation, Mass Variation

Abstract

A method is proposed to compute the theoretical estimation of physical parametersand stability of differential rotation for polytropic starsincluding mass variation. The law of differential rotation is assumed to be in the form ω2 (s) = b1 + b2 s2 + b3 s4 , the angular velocity of rotation (ω) is a function ofdistance (s) of the fluid element from the axis of rotation.Utilizing theconcepts of Roche-equipotential and averaging approachof (Kippenhahnand 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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Published
2019-03-15
Section
Articles