Equation of State of Hot Dense Hyperonic Matter in the Quark-Meson-Coupling (QMC-A) model. (arXiv:1906.11100v3 [nucl-th] UPDATED)

Equation of State of Hot Dense Hyperonic Matter in the Quark-Meson-Coupling (QMC-A) model. (arXiv:1906.11100v3 [nucl-th] UPDATED)
<a href="http://arxiv.org/find/nucl-th/1/au:+Stone_J/0/1/0/all/0/1">J.R.Stone</a>, <a href="http://arxiv.org/find/nucl-th/1/au:+Dexheimer_V/0/1/0/all/0/1">V.Dexheimer</a>, <a href="http://arxiv.org/find/nucl-th/1/au:+Guichon_P/0/1/0/all/0/1">P.A.M.Guichon</a>, <a href="http://arxiv.org/find/nucl-th/1/au:+Thomas_A/0/1/0/all/0/1">A.W.Thomas</a>, <a href="http://arxiv.org/find/nucl-th/1/au:+Typel_S/0/1/0/all/0/1">S.Typel</a>

We report a new equation of state (EoS) of cold and hot hyperonic matter
constructed in the framework of the quark-meson-coupling (QMC-A) model. The
QMC-A EoS yields results compatible with available nuclear physics constraints
and astrophysical observations. It covers the range of temperatures from T=0 to
100 MeV, entropies per particle S/A between 0 and 6, lepton fractions from
Y$_L$=0.0 to 0.6, and baryon number densities n$_B$=0.05-1.2 fm$^{-3}$.
Applications of the QMC-A EoS are made to cold neutron stars (NS) and to hot
proto-neutron stars (PNS) in two scenarios, (i) lepton rich matter with trapped
neutrinos and (ii) deleptonized chemically equilibrated matter. We find that
the QMC-A model predicts hyperons in amounts growing with increasing
temperature and density, thus suggesting not only their presence in PNS but
also, most likely, in NS merger remnants. The nucleon-hyperon phase transition
is studied through the adiabatic index and the speed of sound c$_s$. It is
shown that the lowering of (c$_s$/c)$^2$ to and below the conformal limit of
1/3 is a general consequence of instabilities due to any phase transition and
is not a unique fingerprint of the hadron-quark matter transition. Rigid
rotation of cold and hot stars, their moments of inertia and Kepler frequencies
are also explored.

The QMC-A model results are compared with two relativistic models, the chiral
mean field model (CMF), and the generalized relativistic density functional
with hyperons (GRDF-Y). Similarities and differences are discussed.

We report a new equation of state (EoS) of cold and hot hyperonic matter
constructed in the framework of the quark-meson-coupling (QMC-A) model. The
QMC-A EoS yields results compatible with available nuclear physics constraints
and astrophysical observations. It covers the range of temperatures from T=0 to
100 MeV, entropies per particle S/A between 0 and 6, lepton fractions from
Y$_L$=0.0 to 0.6, and baryon number densities n$_B$=0.05-1.2 fm$^{-3}$.
Applications of the QMC-A EoS are made to cold neutron stars (NS) and to hot
proto-neutron stars (PNS) in two scenarios, (i) lepton rich matter with trapped
neutrinos and (ii) deleptonized chemically equilibrated matter. We find that
the QMC-A model predicts hyperons in amounts growing with increasing
temperature and density, thus suggesting not only their presence in PNS but
also, most likely, in NS merger remnants. The nucleon-hyperon phase transition
is studied through the adiabatic index and the speed of sound c$_s$. It is
shown that the lowering of (c$_s$/c)$^2$ to and below the conformal limit of
1/3 is a general consequence of instabilities due to any phase transition and
is not a unique fingerprint of the hadron-quark matter transition. Rigid
rotation of cold and hot stars, their moments of inertia and Kepler frequencies
are also explored.

The QMC-A model results are compared with two relativistic models, the chiral
mean field model (CMF), and the generalized relativistic density functional
with hyperons (GRDF-Y). Similarities and differences are discussed.

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