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| LaneEmdenStar (const LaneEmdenStar &)=default |
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LaneEmdenStar & | operator= (const LaneEmdenStar &)=default |
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| LaneEmdenStar (LaneEmdenStar &&)=default |
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LaneEmdenStar & | operator= (LaneEmdenStar &&)=default |
| auto | get_clone () const -> std::unique_ptr< evolution::initial_data::InitialData > override |
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| LaneEmdenStar (double central_mass_density, double polytropic_constant) |
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template<typename DataType, typename... Tags> |
| tuples::TaggedTuple< Tags... > | variables (const tnsr::I< DataType, 3 > &x, const double, tmpl::list< Tags... >) const |
| | Retrieve a collection of variables at (x, t)
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| template<typename DataType> |
| tnsr::I< DataType, 3 > | gravitational_field (const tnsr::I< DataType, 3 > &x) const |
| | Compute the gravitational field for the corresponding source term, LaneEmdenGravitationalField.
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const EquationsOfState::PolytropicFluid< false > & | equation_of_state () const |
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void | pup (PUP::er &) override |
| virtual const InitialData & | unwrap () const |
| | Unwrap wrapper types (e.g. WithNoise, which wraps analytic initial data and adds random noise) to reach the underlying analytic solution or data.
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A static spherically symmetric star in Newtonian gravity.
The solution for a static, spherically-symmetric star in 3 dimensions, found by solving the Lane-Emden equation [41] [189] . The Lane-Emden equation has closed-form solutions for certain equations of state; this class implements the solution for a polytropic fluid with polytropic exponent \(\Gamma=2\) (i.e., with polytropic index \(n=1\)). The solution is returned in units where \(G=1\), with \(G\) the gravitational constant.
The radius and mass of the star are determined by the polytropic constant \(\kappa\) and central density \(\rho_c\). The radius is \(R = \pi \alpha\), and the mass is \(M = 4 \pi^2 \alpha^3 \rho_c\), where \(\alpha = \sqrt{\kappa / (2 \pi)}\) and \(G=1\).