Hadron-quark phase transition in neutron star by combining the relativistic Brueckner-Hartree-Fock theory and Dyson-Schwinger equation approach

TL;DR

This paper investigates the hadron-quark phase transition inside neutron stars using advanced theoretical models, analyzing different transition types and their effects on star properties, with implications for observations and gravitational wave data.

Contribution

It combines relativistic Brueckner-Hartree-Fock and Dyson-Schwinger approaches to study phase transitions in neutron stars, exploring both first-order and crossover scenarios with novel interpolation methods.

Findings

No stable quark core in Maxwell construction.

Moderate crossover density region supports 2-solar-mass neutron stars.

Effective medium screening width around 0.35 GeV is necessary.

Abstract

Starting from the relativistic Brueckner-Hartree-Fock theory for nuclear matter and the Dyson-Schwinger equation approach for quark matter, the possible hadron-quark phase transition in the interior of a neutron star is explored. The first-order phase transition and crossover are studied by performing the Maxwell construction and three-window construction respectively. The mass-radius relation and the tidal deformability of the hybrid star are calculated and compared to the joint mass-radius observation of a neutron star and the constraints from gravitational wave detection. For the Maxwell construction, no stable quark core is found in the interior of a neutron star. For the three-window construction, the parameters of the smooth interpolation function are chosen in such a way to keep the thermodynamic stability and lead to a moderate crossover density region. To support a two-solar-mass neutron star under the three-window construction, the effective width of medium screening effects in quark matter should be around $0.35$ GeV.