2015/04/15 by Constantinos Constantinou, Brian Muccioli, Madappa Prakash +1 · 3 citations
Physics and Astronomy · #Astrophysics #Degenerate energy levels #Gamma-ray bursts and supernovae #Isospin #Neutron #Neutron star #Nuclear matter #Nuclear physics #Nuclear physics research studies #Nucleon #Particle physics #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Range (aeronautics) #Saturation (graph theory) #Thermal #Thermodynamics #Yukawa potential #astro-ph.SR #nucl-th
paper · pdf · doi:10.1103/physrevc.92.025801
47 pages, 40 figures
arxiv created 2015/04/15 · openalex publication_date 2015/08/05 · arxiv updated 2015/08/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We explore the thermal properties of hot and dense matter using a model that reproduces the empirical properties of isospin symmetric and asymmetric bulk nuclear matter, optical-model fits to nucleon-nucleus scattering data, heavy-ion flow data in the energy range 0.5--2 GeV/A, and the largest well-measured neutron star mass of 2M_\ensuremath\bigodot. This model, which incorporates finite range interactions through a Yukawa-type finite range force, is contrasted with a conventional zero range Skyrme model. Both models predict nearly identical zero-temperature properties at all densities and proton fractions, including the neutron star maximum mass, but differ in their predictions for heavy-ion flow data. We contrast their predictions of thermal properties, including their specific heats, and provide analytical formulas for the strongly degenerate and nondegenerate limits. We find significant differences in the results of the two models for quantities that depend on the density derivatives of nucleon effective masses. We show that a constant value for the ratio of the thermal components of pressure and energy density expressed as \mathrm\ensuremathΓth=1+(Pth/\ensuremathεth), often used in simulations of proto-neutron stars and merging compact object binaries, fails to adequately describe results of either nuclear model. The region of greatest discrepancy extends from subsaturation densities to a few times the saturation density of symmetric nuclear matter. Our results suggest alternate approximations for the thermal properties of dense matter that are more realistic.