Thermodynamic instabilities and statistical effects in protoneutron stars

G Gervino,A Lavagno,D Pigato

doi:10.1088/1742-6596/880/1/012062

Abstract

We investigate the physical properties of the protoneutron stars in the framework of a relativistic mean-field model and we study the finite-temperature equation of state in β-stable matter at fixed entropy per baryon, in the presence of hyperons, Δ-isobar resonances and trapped neutrinos. In this context, we study the possible presence of thermodynamic instabilities and a phase transition from nucleonic matter to resonance-dominated Δ-matter can take place. Such a phase transition is characterized by both mechanical instability (fluctuations on the baryon density) and by chemical-diffusive instability (fluctuations on the isospin concentration) in asymmetric nuclear matter. We show that such statistical effects could play a crucial role in the structure and in the evolution of the protoneutron stars.

Highlights

A protoneutron star (PNS) is formed in a stellar remnant after a successful core-collapse supernova explosion of a star with a mass smaller than about 20 solar masses and in the first seconds of its evolution it is a very hot, lepton rich and β-stable object and a lepton concentration typical of the pre-supernova matter [1].The knowledge of the nuclear equation of state (EOS) of dense matter at finite temperature plays a crucial role in the determination of the structure and in the macrophysical evolution of the PNS [2]
We investigate the physical properties of the protoneutron stars in the framework of a relativistic mean-field model and we study the finite-temperature equation of state in β-stable matter at fixed entropy per baryon, in the presence of hyperons, ∆-isobar resonances and trapped neutrinos
We study the possible presence of thermodynamic instabilities and a phase transition from nucleonic matter to resonance-dominated ∆-matter can take place

Summary

Related content

- Power-law distributions in protoneutron stars G Gervino, A Lavagno and D Pigato. - Evolutionary Sequences of Rotating Protoneutron Stars with Hyperons Ye-Fei Yuan and Jeremy S. - Power-law distributions in protoneutron stars G Gervino, A Lavagno and D Pigato. - Evolutionary Sequences of Rotating Protoneutron Stars with Hyperons Ye-Fei Yuan and Jeremy S. View the article online for updates and enhancements. This content was downloaded from IP address 193.205.65.86 on 11/09/2017 at 10:20

Introduction

Published under licence by IOP Publishing Ltd

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Results and discussion

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