Reconciling Multi-messenger Constraints with Chiral Symmetry Restoration

TL;DR

This paper demonstrates that a purely hadronic equation of state, incorporating chiral symmetry restoration, can satisfy multi-messenger astrophysical constraints on neutron star structure without requiring a hadron-quark phase transition.

Contribution

It introduces a parity doublet model for nucleonic and delta matter that aligns neutron star observations with chiral symmetry considerations in a hadronic framework.

Findings

Purely hadronic EOS can meet astrophysical constraints

Chiral symmetry restoration is self-consistently included

No need for hadron-quark phase transition in models

Abstract

We consider the parity doublet model for nucleonic and delta matter to investigate the structure of neutron stars. We show that it is possible to reconcile the multi-messenger astronomy constraints within a purely hadronic equation of state (EOS), which accounts for the self-consistent treatment of the chiral symmetry restoration in the baryonic sector. We demonstrate that the characteristics of the EOS required by the astrophysical constraints do not necessarily imply the existence of a hadron-quark phase transition in the stellar core.