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eos

This page contains a full reference of all parameters available for the eos module. At the bottom of the page you can find an example parameter block that can be used in your parameter file.

eos

EOS parameters

Name:	eos_type
Type:	keyword
Default:	hybrid
Range:	ideal_gas, hybrid, tabulated
Description:	Kind of EOS

ideal_gas_eos

Parameters for the ideal gas eos

Name:	gamma
Type:	double
Default:	2
Range:	(1,*)
Description:	Adiabatic index

Name:	entropy_min
Type:	double
Default:	1e-12
Range:	(0,*)
Description:	Lower bound on entropy to avoid log(0)

Name:	kappa_id
Type:	double
Default:	0
Range:	[0,*)
Description:	If the initial data is a polytrope, kappa of that polytrope in geom units

hybrid_eos

Parameters for the hybrid eos

Name:	cold_eos_type
Type:	keyword
Default:	piecewise_polytrope
Range:	piecewise_polytrope, tabulated
Description:	For hybrid_eos: kind of cold eos

Name:	gamma_th
Type:	double
Default:	1.8
Range:	(*,*)
Description:	Thermal Gamma for hybrid eos

piecewise_polytrope

Piecewise polytrope parameters

Name:	n_pieces
Type:	unsigned int
Default:	7
Range:	[1,*)
Description:	Number of pieces

Name:	gammas
Type:	list
Default:	[1.58425, 1.28733, 0.62223, 1.35692, 3.005, 2.988, 2.851]
Range:	(0,*)
Description:	Gammas of piecewise polytrope

Name:	rhos
Type:	list
Default:	[3.951156e-11, 6.12596e-07, 4.254672e-06, 0.0002367449, 0.0008114721, 0.0016191]
Range:	(0,*)
Description:	rhos of piecewise polytrope

Name:	kappa_0
Type:	double
Default:	168.5819
Range:	[0,*)
Description:	Kappa of first piece

tabulated_eos

Parameters for nuclear tabulated eos

Name:	table_filename
Type:	string
Default:	blah.h5
Description:	File name of tabulated eos

Name:	table_format
Type:	keyword
Default:	compose
Range:	compose, stellarcollapse
Description:	Format of 3D table

Name:	cold_table_filename
Type:	string
Default:	blah.grace
Description:	Cold slice table file name

Name:	force_mu
Type:	bool
Default:	True
Description:	If true (default), interpret the table’s rho axis using the atomic mass unit (m_u = 931.494 MeV/c^2) for the nb <-> rho conversion, matching the FUKA / LORENE / Margherita convention used by virtually all GR-MHD initial-data codes. The cold EOS table must have been generated with the same convention (use force_mu=True in GRACEpy). Set to false ONLY for pure CompOSE-strict thermodynamics work where no FUKA-format initial data is involved; importing FUKA initial data with force_mu=false produces a ~1% baryonic mass error and a corresponding ~1 rad GW phase drift over a typical BNS inspiral.

Name:	sanitize_axes
Type:	bool
Default:	True
Description:	If true (default), regenerate the interior points of the log(nb), log(T), and Y_e axes uniformly between their stored endpoints after ingest. This removes FP32->FP64 quantization jitter from tables that were written with single-precision axes, which would otherwise make the axis spacing non-uniform at the bit level and bias the table’s (uniform-spacing) index-lookup arithmetic. Requires the axis to be uniform in its canonical transform space (log for nb and T, linear for Y_e) – this matches the CompOSE convention. A warning is emitted if the original spacing deviates from uniform by more than a small relative tolerance.

Name:	eps_maximum
Type:	double
Default:	1.e5
Range:	(0,*)
Description:	Maximum allowed specific internal energy

Name:	entropy_minimum
Type:	double
Default:	1e-13
Range:	(0,*)
Description:	Minimum allowed entropy per particle