Isothermal vs. isentropic description of protoneutron stars in the Brueckner-Bethe-Goldstone theory

TL;DR

This paper compares isothermal and isentropic models of protoneutron stars using the Brueckner-Bethe-Goldstone approach, finding similar particle populations and equations of state, with minimal impact on maximum mass.

Contribution

It provides a detailed comparison of isothermal and isentropic descriptions of protoneutron stars within a sophisticated many-body theoretical framework.

Findings

Particle populations are similar in both models.

Equation of state shows little difference between profiles.

Maximum mass is nearly unaffected by temperature or entropy assumptions.

Abstract

We study the structure of hadronic protoneutron stars within the finite temperature Brueckner-Bethe-Goldstone theoretical approach. Assuming beta-equilibrated nuclear matter with nucleons and leptons in the stellar core, with isothermal or isentropic profile, we show that particle populations and equation of state are very similar. As far as the maximum mass is concerned, we find that its value turns out to be almost independent on T, while a slight decrease is observed in the isentropic case, due to the enhanced proton fraction in the high density range.