Nonlinear nuclear equation of state and thermodynamical instabilities in warm and dense nuclear matter

In this paper, we investigate the cooling of neutron stars with relativistic and nonrelativistic models of dense nuclear matter. We focus on the effects of uncertainties originated from the nuclear models, the composition of elements in the envelope region, and the formation of superfluidity in the core and the crust of neutron stars. Discovery of [Formula: see text] neutron stars PSR J1614−2230 and PSR J0343[Formula: see text]0432 has triggered the revival of stiff nuclear equation of state at high densities. In the meantime, observation of a neutron star in Cassiopeia A for more than 10 years has provided us with very accurate data for the thermal evolution of neutron stars. Both mass and temperature of neutron stars depend critically on the equation of state of nuclear matter, so we first search for nuclear models that satisfy the constraints from mass and temperature simultaneously within a reasonable range. With selected models, we explore the effects of element composition in the envelope region, and the existence of superfluidity in the core and the crust of neutron stars. Due to uncertainty in the composition of particles in the envelope region, we obtain a range of cooling curves that can cover substantial region of observation data.

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Delta and pion abundances in hot dense nuclear matter and the nuclear equation of state

Physics Letters B ◽

10.1016/0370-2693(88)90070-6 ◽

1988 ◽

Vol 201 (1) ◽

pp. 11-16 ◽

Cited By ~ 16

Author(s):

M. Cubero ◽

M. Schönhofen ◽

H. Feldmeier ◽

W. Nörenberg

Keyword(s):

Equation Of State ◽

Nuclear Matter ◽

Nuclear Equation Of State ◽

Dense Nuclear Matter

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Constraining the equation of state of dense nuclear matter using thermal emission of neutron stars

Journal of Physics Conference Series ◽

10.1088/1742-6596/1667/1/012001 ◽

2020 ◽

Vol 1667 ◽

pp. 012001

Author(s):

Nicolas Baillot d’Étivaux ◽

Jérôme Margueron ◽

Sebastien Guillot ◽

Natalie Webb ◽

Màrcio Catelan ◽

...

Keyword(s):

Equation Of State ◽

Neutron Stars ◽

Nuclear Matter ◽

Thermal Emission ◽

Dense Nuclear Matter

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The Nuclear Equation of State in Heavy Ion Collisions

HNPS Proceedings ◽

10.12681/hnps.2970 ◽

2020 ◽

Vol 13 ◽

pp. 203

Author(s):

T. Gaitanos ◽

M. Colonna ◽

M. Di Toro ◽

H. H. Wolter

Keyword(s):

Equation Of State ◽

Nuclear Matter ◽

Ground State ◽

Heavy Ion Collisions ◽

Reaction Dynamics ◽

Heavy Ion ◽

Intermediate Energy ◽

Nuclear Equation Of State ◽

Ion Collisions ◽

Theoretical Results

We present several possibilities offered by the dynamics of intermediate energy heavy ion collisions to investigate the nuclear matter equation of state (EoS) beyond the ground state. In particular the relation between the reaction dynamics and the high density nuclear EoS is discussed by comparing theoretical results with experiments.

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The Physics of Supernovae and the Equation of State of Dense Nuclear Matter

Advances in Theoretical Physics ◽

10.1016/b978-0-08-036940-2.50018-7 ◽

1990 ◽

pp. 193-213

Author(s):

G.E. BROWN

Keyword(s):

Equation Of State ◽

Nuclear Matter ◽

Dense Nuclear Matter

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VIRIAL EXPANSION OF THE NUCLEAR EQUATION OF STATE

International Journal of Modern Physics E ◽

10.1142/s0218301312500061 ◽

2012 ◽

Vol 21 (01) ◽

pp. 1250006 ◽

Cited By ~ 3

Author(s):

RUSLAN MAGANA ◽

HUA ZHENG ◽

ALDO BONASERA

Keyword(s):

Phase Transition ◽

Equation Of State ◽

Nuclear Matter ◽

Order Phase Transition ◽

Quark Gluon Plasma ◽

Ground State ◽

Gluon Plasma ◽

Second Order ◽

Nuclear Equation Of State ◽

Second Order Phase Transition

We study the equation of state (EOS) of nuclear matter as function of density. We expand the energy per particle (E/A) of symmetric infinite nuclear matter in powers of the density to take into account 2, 3, …, N-body forces. New EOS are proposed by fitting ground state properties of nuclear matter (binding energy, compressibility and pressure) and assuming that at high densities a second-order phase transition to the quark–gluon plasma (QGP) occurs. The latter phase transition is due to symmetry breaking at high density from nuclear matter (locally color white) to the QGP (globally color white). In the simplest implementation of a second-order phase transition we calculate the critical exponent δ by using Landau's theory of phase transition. We find δ = 3. Refining the properties of the EOS near the critical point gives δ = 5 in agreement with experimental results. We also discuss some scenarios for the EOS at finite temperatures.

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Non-Linear Derivative Interactions in Relativistic Hadrodynamics

HNPS Proceedings ◽

10.12681/hnps.2539 ◽

2019 ◽

Vol 18 ◽

pp. 63

Author(s):

T. Gaitanos ◽

M. Kaskulov

Keyword(s):

Equation Of State ◽

Nuclear Matter ◽

Density Dependence ◽

Energy Dependence ◽

Optical Potential ◽

The Novel ◽

Nuclear Equation Of State ◽

Dirac Phenomenology ◽

Non Linear

The Lagrangian of Relativistic Hadrodynamics (RHD) is extended by introducing non-linear derivative (NLD) operators into the interactions between the nucleon with the meson elds. As the novel feature of the NLD model, the nucleon selfenergy depends on both, on energy and density. Our approach contains a single cut-o parameter, which determines the density dependence of the nuclear equation of state (EoS) and the energy dependence of the nucleon-nucleus optical potential. The NLD formalism is compatible with results from microscopic nuclear matter calculations as well as with Dirac phenomenology.

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Chiral Effective Field Theory and the High-Density Nuclear Equation of State

Annual Review of Nuclear and Particle Science ◽

10.1146/annurev-nucl-102419-041903 ◽

2021 ◽

Vol 71 (1) ◽

Author(s):

C. Drischler ◽

J.W. Holt ◽

C. Wellenhofer

Keyword(s):

Field Theory ◽

Equation Of State ◽

Neutron Stars ◽

Nuclear Matter ◽

Effective Field Theory ◽

Effective Field ◽

High Density ◽

Chiral Effective Field Theory ◽

Nuclear Equation Of State ◽

Density Regime

Born in the aftermath of core-collapse supernovae, neutron stars contain matter under extraordinary conditions of density and temperature that are difficult to reproduce in the laboratory. In recent years, neutron star observations have begun to yield novel insights into the nature of strongly interacting matter in the high-density regime where current theoretical models are challenged. At the same time, chiral effective field theory has developed into a powerful framework to study nuclear matter properties with quantified uncertainties in the moderate-density regime for modeling neutron stars. In this article, we review recent developments in chiral effective field theory and focus on many-body perturbation theory as a computationally efficient tool for calculating the properties of hot and dense nuclear matter. We also demonstrate how effective field theory enables statistically meaningful comparisons among nuclear theory predictions, nuclear experiments, and observational constraints on the nuclear equation of state. Expected final online publication date for the Annual Review of Nuclear and Particle Science, Volume 71 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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Thermal properties of hot and dense matter: Influence of rapid rotation on protoneutron stars, hot neutron stars, and neutron star merger remnants

EPJ Web of Conferences ◽

10.1051/epjconf/202125205004 ◽

2021 ◽

Vol 252 ◽

pp. 05004

Author(s):

Polychronis Koliogiannis ◽

Charalampos Moustakidis

Keyword(s):

Neutron Star ◽

Equation Of State ◽

Neutron Stars ◽

Nuclear Matter ◽

Equations Of State ◽

Interaction Model ◽

Dense Matter ◽

Baryon Density ◽

Dense Nuclear Matter ◽

Protoneutron Stars

The knowledge of the equation of state is a key ingredient for many dynamical phenomena that depend sensitively on the hot and dense nuclear matter, such as the formation of protoneutron stars and hot neutron stars. In order to accurately describe them, we construct equations of state at FInite temperature and entropy per baryon for matter with varying proton fractions. This procedure is based on the momentum dependent interaction model and state-of-the-art microscopic data. In addition, we investigate the role of thermal and rotation effects on microscopic and macroscopic properties of neutron stars, including the mass and radius, the frequency, the Kerr parameter, the central baryon density, etc. The latter is also connected to the hot and rapidly rotating remnant after neutron star merger. The interplay between these quantities and data from late observations of neutron stars, both isolated and in matter of merging, could provide useful insight and robust constraints on the equation of state of nuclear matter.

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Equation of state of dense nuclear matter and neutron star structure from nuclear chiral interactions

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731604 ◽

2018 ◽

Vol 609 ◽

pp. A128 ◽

Cited By ~ 27

Author(s):

Ignazio Bombaci ◽

Domenico Logoteta

Keyword(s):

Neutron Star ◽

Equation Of State ◽

Neutron Stars ◽

Nuclear Matter ◽

Symmetric Nuclear Matter ◽

Heavy Nuclei ◽

Hartree Fock ◽

Binary Neutron Star ◽

Dense Nuclear Matter ◽

Three Body

Aims. We report a new microscopic equation of state (EOS) of dense symmetric nuclear matter, pure neutron matter, and asymmetric and β-stable nuclear matter at zero temperature using recent realistic two-body and three-body nuclear interactions derived in the framework of chiral perturbation theory (ChPT) and including the Δ(1232) isobar intermediate state. This EOS is provided in tabular form and in parametrized form ready for use in numerical general relativity simulations of binary neutron star merging. Here we use our new EOS for β-stable nuclear matter to compute various structural properties of non-rotating neutron stars. Methods. The EOS is derived using the Brueckner–Bethe–Goldstone quantum many-body theory in the Brueckner–Hartree–Fock approximation. Neutron star properties are next computed solving numerically the Tolman–Oppenheimer–Volkov structure equations. Results. Our EOS models are able to reproduce the empirical saturation point of symmetric nuclear matter, the symmetry energy Esym, and its slope parameter L at the empirical saturation density n0. In addition, our EOS models are compatible with experimental data from collisions between heavy nuclei at energies ranging from a few tens of MeV up to several hundreds of MeV per nucleon. These experiments provide a selective test for constraining the nuclear EOS up to ~4n0. Our EOS models are consistent with present measured neutron star masses and particularly with the mass M = 2.01 ± 0.04 M⊙ of the neutron stars in PSR J0348+0432.

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