Many-body effects on dense matter with hyperons at finite temperature

TL;DR

This paper extends the Many-Body Forces model to finite temperature, incorporating hyperons and exploring implications for nuclear matter and proto-neutron stars in a relativistic framework.

Contribution

It introduces the first finite-temperature extension of the MBF model with new hyperon coupling schemes and analyzes their effects on nuclear matter and stellar properties.

Findings

Finite temperature affects the speed of sound and compressibility.

Hyperon interactions significantly influence the mass-radius relation of neutron stars.

The model provides new insights into proto-neutron star properties.

Abstract

In this work, we present the first extension of the Many-Body Forces (MBF) Model to finite temperature. The MBF Model describes nuclear matter in a relativistic quantum hadrodynamics formalism that takes many-body forces into account through a field dependence of the nuclear interaction coupling constants. Assuming nuclear matter to be charge neutral, beta-equilibrated, and populated by the baryon octet, electrons, and muons, we explore the parameters of the model, three different hyperon coupling schemes (also introduced here for the first time in MBF), and temperature effects to describe basic properties of nuclear matter, including the speed of sound, compressibility, and adiabatic index. We also investigate the mass-radius relation of compact stars by solving the Tolman-Oppenheimer-Volkoff equations at zero and finite temperature, including scenarios with fixed entropy per baryon. Our original results at finite temperature open the path to a new description of proto-neutron stars.