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arXiv · 1810.04245

Neutron stars meet constraints from high and low energy nuclear physics

V. Sagun·I. Lopes·A. Ivanytskyi
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Abstract

A novel equation of state used for analysis of the heavy ion collision experimental data is generalized to also describe the matter inside neutron stars. This approach differs from others by including an induced surface tension caused by the short range repulsion between particles accounted by presence of their hard cores. This new equation of state respects thermodynamic consistency and is free from the usual causality problems. This makes it applicable over a wide range of temperatures and baryon densities, including the ones inside neutron stars. Despite small number of parameters the present equation of state reproduces properties of the saturated nuclear matter and is consistent with the proton flow constraint as well as with astrophysical data obtained from neutron star observations. Accordingly, we found the sets of parameters that agree with the same ones obtained from the heavy ion collision data analysis.

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V. Sagun, I. Lopes, A. Ivanytskyi. 2018-10-09. Neutron stars meet constraints from high and low energy nuclear physics. https://doi.org/10.1016/j.nuclphysa.2018.10.024

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