Diquark and chiral condensate in a self-consistent NJL-type model

Wen-Li Yuan, Jingyi Chao, Ang Li

Published 2023-04-24Version 1

In this work, a modified NJL-type model is used, in which the contact current-current interaction is Fierz-transformed into quark-antiquark interactions $\mathcal{F}_{\bar{q} q}=(\bar{q} \hat{O} q)^{2}$ and quark-quark interactions $\mathcal{F}_{q q}=(q \hat{O} q)^{2}$, which are directly related to the chiral condensate and diquark condensate, respectively. Under mean-field approximation, the chiral condensate and the diquark condensate are studied on the same footing. We discuss in detail the competition between the chiral condensate and the diquark condensate, as well as the order of the chiral phase transition by analyzing the resulting chiral susceptibility.