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The code public_poly.tbz computes the structure of stars that are in hydrostatic equilibrium and obey a polytropic equation of state \begin{equation} P = K \rho^{\gamma} = K \rho^{1 + 1/n} \ . \label{eq1} \tag{1} \end{equation} The solution to the resulting LaneEmden equation \begin{equation} \dfrac{d^2y}{dx^2} + \dfrac{2}{x} \dfrac{dy}{dx} + y^n = 0 \hskip 0.5in y(x=0)=1 \hskip 0.5in \left . \dfrac{dy}{dx}\right _{x=0} = 0 \ , \label{eq2} \tag{2} \end{equation} where $x$ is a dimensionless radius and $y$ is a dimensionless density, is writen out in dimensionless form and in physical units. Certain polytropic stars are related cold white dwarfs.



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