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APR_SRO (SNA version)


This table contains the EoS by Schneider et al [SCMP_2019] computed using the APR model [APRP_1998]. The EoS has been constructed extending the approach of Schneider, Roberts & Ott [SRO_17"]. The model includes nucleons, which are treated as non-relativistic particles; alpha-particles, modeled as hard spheres of volume 24 /fm^3 forming an ideal Boltzmann gas; and photos, electrons, and positrons, all treated as thermally equilibrated non-interacting relativistic gases. At low densities and temperatures nucleons may cluster into heavy nuclei computed within the single nuclues approximation (SNA). In the SNA, one representative nucleus or, more generally, a high-density structure such as a pasta phase, is determined from equilibrium conditions within a spherical Wigner-Seitz cell, including surface, Coulomb, and translational energy corrections using a liquid-drop model for the surface corrections. The Wigner-Seitz cell is charge neutral, and heavy nuclei are surrounded by a gas of free nucleons, alpha-particles, photons, electrons and positrons. Interactions between the outside gas and the nuclei are taken into account through an excluded volume. At high densities and temperatures heavy nuclei or the pasta phases dissolve in favor of homogeneous nuclear matter. The configuration of matter and the balance between the different phases is given by the thermodynamically most favorable state, that is, the one that minimizes the Helmholtz free energy of the system and, thus, guarantees thermodynamic consistency of the EoS. Transitions from inhomogeneous to bulk nuclear matter are first order and simply chosen from the phase which minimizes the Helmholtz free energy. Further details can be found in Refs.~[SCMP_2019,SRO_17"]. A link to additional information which includes the open-source SROEOS code and pre-computed tables can be found on Stellarcollapse . Tables where a transition from the SNA treatment to one considering 3 335 nuclei in nuclear statistical equilibrium (NSE) are also available.

Nparam = 3
Particles = npeN
T min = 9.99e-03
T max = 2.51e+02
T pts = 133
nb min = 5.43e-13
nb max = 6.32e+00
nb pts = 393
Y min = 5.00e-03
Y max = 6.55e-01
Y pts = 66


References to the original work:
[APRP_1998]   A. Akmal, V. R. Pandharipande and D. G. Ravenhall, Phys. Rev. C 58, 1804 (1998)
[SRO_17]   A.S. Schneider, L. Roberts, C.D. Ott, Phys.Rev. C96, 065802 (2017)
[SCMP_2019]   A.S. Schneider, C. Constantinou, B. Muccioli, M. Prakash, arXiv:1901.09652 (2019)

Data sheet

Data (contains all following files and data sheet)

The EoS "APR_SRO (SNA version)" has not eos.init file associated so computation is not possible.

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