jesterTOV.eos.metamodel.MetaModel_with_peakCSE_EOS_model

jesterTOV.eos.metamodel.MetaModel_with_peakCSE_EOS_model#

class MetaModel_with_peakCSE_EOS_model(
nsat=0.16,
nmin_MM_nsat=0.75,
nmax_nsat=12,
ndat_metamodel=100,
ndat_CSE=100,
**metamodel_kwargs,
)[source]#

Bases: Interpolate_EOS_model

Meta-model EOS with Gaussian peak Constant Speed-of-sound Extensions (peakCSE).

This class implements a sophisticated CSE parametrization based on the peakCSE model, which combines a Gaussian peak structure with logistic growth to model phase transitions while ensuring asymptotic consistency with perturbative QCD (pQCD) at the highest densities.

Mathematical Framework: The speed of sound squared is parametrized as:

\[c^2_s &= c^2_{s,{\rm break}} + \frac{\frac{1}{3} - c^2_{s,{\rm break}}}{1 + e^{-l_{\rm sig}(n - n_{\rm sig})}} + c^2_{s,{\rm peak}}e^{-\frac{1}{2}\left(\frac{n - n_{\rm peak}}{\sigma_{\rm peak}}\right)^2}\]

Reference: Greif:2018njt, arXiv:1812.08188

Note

The peakCSE model provides greater physical realism than simple piecewise-constant CSE by incorporating smooth transitions and theoretically motivated high-density behavior.

__init__(
nsat=0.16,
nmin_MM_nsat=0.75,
nmax_nsat=12,
ndat_metamodel=100,
ndat_CSE=100,
**metamodel_kwargs,
)[source]#

Initialize the MetaModel with peakCSE extensions for realistic phase transition modeling.

This constructor sets up the peakCSE model that combines meta-model physics at low-to-intermediate densities with sophisticated Gaussian peak + logistic growth extensions at high densities, designed to model phase transitions while maintaining consistency with perturbative QCD predictions.

Parameters:

  • nsat (Float, optional) – Nuclear saturation density \(n_0\) [\(\mathrm{fm}^{-3}\)]. Reference density for the meta-model construction. Defaults to 0.16.

  • nmin_MM_nsat (Float, optional) – Starting density for meta-model region as fraction of \(n_0\). Must be above crust-core transition. Defaults to 0.75 (= 0.12/0.16).

  • nmax_nsat (Float, optional) – Maximum density for EOS construction in units of \(n_0\). Should extend to densities where pQCD limit is approached. Defaults to 12.

  • ndat_metamodel (Int, optional) – Number of density points for meta-model region discretization. Higher values give smoother meta-model interpolation. Defaults to 100.

  • ndat_CSE (Int, optional) – Number of density points for peakCSE region discretization. Controls resolution of phase transition and pQCD approach modeling. Defaults to 100.

  • **metamodel_kwargs – Additional keyword arguments passed to the underlying MetaModel_EOS_model. Includes parameters like kappas, v_nq, b_sat, b_sym, crust_name, etc. See MetaModel_EOS_model.__init__ for complete parameter descriptions.

See also

MetaModel_EOS_model.__init__ : Base meta-model parameters construct_eos : Method that defines peakCSE parameters and break density

Methods

__init__([nsat, nmin_MM_nsat, nmax_nsat, ...])

Initialize the MetaModel with peakCSE extensions for realistic phase transition modeling.

construct_eos(params)

Construct the complete EOS using meta-model + peakCSE extensions.

get_required_parameters()

Return list of parameter names needed for this EOS.

interpolate_eos(n, p, e)

Convert physical EOS quantities to geometric units and compute auxiliary quantities.

offset_calc(nbreak, cs2_break, params)

construct_eos(params)[source]#

Construct the complete EOS using meta-model + peakCSE extensions.

This method builds the full EOS by combining the meta-model approach with peakCSE extensions that model phase transitions through Gaussian peaks and approach the pQCD conformal limit at high densities.

Parameters:

params (dict) –

Combined parameters including:

  • Nuclear empirical parameters (NEP) for meta-model construction

  • ’nbreak’ key specifying the transition density between meta-model and peakCSE regions

  • peakCSE model parameters defining high-density behavior (gaussian_peak, gaussian_mu, gaussian_sigma, logit_growth_rate, logit_midpoint)

Returns:

EOSData – Complete EOS data containing ns, ps, hs, es, dloge_dlogps, cs2, mu

Note

The peakCSE speed of sound follows:

\[c^2_s = c^2_{s,{\rm break}} + \frac{\frac{1}{3} - c^2_{s,{\rm break}}}{1 + e^{-l_{\rm sig}(n - n_{\rm sig})}} + c^2_{s,{\rm peak}}e^{-\frac{1}{2}\left(\frac{n - n_{\rm peak}}{\sigma_{\rm peak}}\right)^2}\]

This ensures smooth transitions, realistic phase transition modeling, and asymptotic consistency with the pQCD conformal limit \(c_s^2 = 1/3\).

offset_calc(nbreak, cs2_break, params)[source]#
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