jesterTOV.tov.anisotropy.AnisotropyTOVSolver

jesterTOV.tov.anisotropy.AnisotropyTOVSolver#

class AnisotropyTOVSolver[source]#

Bases: TOVSolverBase

Post-TOV solver with phenomenological beyond-GR corrections.

Solves post-TOV equations with correction term sigma:

\[\frac{dp}{dr} = -\frac{[\varepsilon(r) + p(r)][m(r) + 4\pi r^3 p(r)]}{r[r - 2m(r)]} - \frac{2\sigma(r)}{r}\]

The sigma function includes three independently parametrized models (Rahmansyah et al. 2020, Eqs. 12–14):

  • Bowers & Liang 1974 (lambda_BL)

  • Horvat, Ilijic & Marunovic 2011 (lambda_DY)

  • Cosenza et al. 1981 (lambda_HB)

__init__()#

Methods

__init__()

construct_family(eos_data, ndat, min_nsat[, ...])

Construct M-R-Λ curves by solving for multiple central pressures.

fetch_params(params)

Extract solver-specific parameters from the combined EOS+TOV parameter dict.

get_required_parameters()

Anisotropy solver requires 3 additional coupling parameters.

solve(eos_data, pc, tov_params)

Solve post-TOV equations for given central pressure.
get_required_parameters()[source]#

Anisotropy solver requires 3 additional coupling parameters.

Return type:

list[str]

Returns:

list[str] –

[“lambda_BL”, “lambda_DY”, “lambda_HB”] corresponding to

the Bowers-Liang, Horvat et al., and Cosenza et al. models. Set to 0.0, 0.0, and 1.0 respectively to recover the standard isotropic GR equations.

solve(eos_data, pc, tov_params)[source]#

Solve post-TOV equations for given central pressure.

This function integrates the post-TOV equations that include beyond-GR corrections. The integration procedure is identical to the standard TOV case, but the differential equations include additional sigma terms.

Parameters:
Return type:

TOVSolution

Returns:

TOVSolution –

Mass, radius, and Love number in geometric units.

Returns NaN values on solver failure (JAX-compatible).

Notes

The modifications affect the stellar structure but the same integration method and boundary conditions as the standard TOV case are used.