Chiral phase transition and equation of state in chiral imbalance * *Supported by the National Natural Science Foundation of China (11475085, 11535005, 11690030, 11873030, 11905104) and the Fostering Program in Disciplines Possessing Novel Features for Natural Science (2020SCUNL209)

Abstract

The chiral phase transition and equation of state are studied within a novel self-consistent mean-field approximation of the two-flavor Nambu-Jona-Lasinio model. In this newly developed model, modifications to the chemical μ and chiral chemical potentials are naturally included by introducing vector and axial-vector channels from Fierz-transformed Lagrangian to the standard Lagrangian. In the proper-time scheme, the chiral phase transition is a crossover in the plane. However, when is incorporated, our study demonstrates that a first order phase transition may emerge. Furthermore, the chiral imbalance will soften the equation of state of quark matter. The mass-radius relationship and tidal deformability of quark stars are calculated. The maximum mass and radius decrease as increases. Our study also indicates that the vector and axial-vector channels exhibit an opposite influence on the equation of state.