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Equilibrium sequences of irrotational binary polytropic stars : The case of double polytropic stars

Keisuke Taniguchi·Takashi Nakamura
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Abstract

Solutions to equilibrium sequences of irrotational binary polytropic stars in Newtonian gravity are expanded in a power of $ε=a_0/R$, where R and $a_0$ are the orbital separation of the binary system and the radius of each star for $R=\infty$. For each order of $ε$, we should solve ordinary differential equations for arbitrary polytropic indices n. We show solutions for polytropic indices n= 0.5, 1, 1.5 and 2 up to $ε^6$ orders. Our semi-analytic solutions can be used to check the validity of numerical solutions.

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Keisuke Taniguchi, Takashi Nakamura. 2000-04-03. Equilibrium sequences of irrotational binary polytropic stars : The case of double polytropic stars. https://doi.org/10.1103/physrevd.62.044040

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