On the energy budget of the transition of a neutron star into the third family branch

TL;DR

This paper investigates the energy released during the transition of neutron stars into a third family branch, considering different equations of state and their astrophysical implications.

Contribution

It introduces a detailed analysis of energy budgets during neutron star transitions using specific EoS models, including phase transitions to quark matter, and compares different model scenarios.

Findings

Energy release ranges from 10^{49} to 10^{52} ergs.

Different EoS models affect the maximum energy and radius differences.

Transitions could have observable astrophysical signatures.

Abstract

Transition of a compact star into the third family for an equation of state (EoS) featuring mass twins is considered. The energy released at a baryon number conserving transition for static compact stars configurations is computed for two sets of models for comparison. The EoS of choice is the density dependent functional DD2 EoS with excluded model correction for hadronic matter which suffers a phase transition into deconfined quark matter described by a constant speed of sound approach. The two sets of EoS models feature different compact star mass onsets that maximize the energy and radius difference at the transition while simultaneously fulfilling state-of-the-art constraints from multi-messenger astronomy and empirical nuclear data. It is found that the maximal energy budget at the transitions falls in the range of $10^{49}$ - $10^{52}$ ergs.