Extended parity doublet model with a new transport code

Abstract

A new transport code "DaeJeon Boltzmann-Uehling-Uhlenbeck" (DJBUU) has been developed and enables us to describe the dynamics of heavy-ion collisions in the low-energy region. To confirm the validity of the new code, we first calculate Au + Au collisions at E-beam = 100A and 400A MeV and also perform the box calculation to check the detail of collisions and Pauli blocking without using a mean-field potential as suggested by the Transport Code Comparison Project. After confirming the validity of new transport code, we study low-energy heavy-ion collisions by using an extended parity doublet model. Since the distinctive feature of the parity doublet model is the existence of the chiral-invariant mass that contributes to the nucleon mass, we investigate how physical quantities depend on the chiral-invariant mass in heavy-ion collisions at low energies. For this, we calculate physical quantities such as the effective nucleon mass in central collisions and transverse flow in semicentral collisions of Au + Au at E-beam = 400A MeV with different values of the chiral-invariant masses.