QCD critical end point from a realistic PNJL model

¹ Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
² University of Chinese Academy of Sciences, Beijing 100049, China

^* e-mail: xukun@ihep.ac.cn
^** e-mail: lizb@ihep.ac.cn
^*** e-mail: huangm@ihep.ac.cn

Published online: 14 November 2018

Abstract

With parameters fixed by critical temperature and equation of state at zero baryon chemical potential, a realistic Polyakov-Nambu-Jona-Lasinio (rPNJL) model predicts a critical end point of chiral phase transition at (μ^E_B = 720MeV; T^E = 93MeV). The extracted freeze-out line from heavy ion collisions is close to the chiral phase transition boundary in the rPNJL model, and the kurtosis kσ² of baryon number fluctuations from the rPNJL model along the experimental freeze-out line agrees well with the BES-I measurement. Our analysis shows that the dip structure of measured kσ² is determined by the relationship between the freeze-out line and chiral phase transition line at low baryon density region, and the peak structure can be regarded as a clean signature for the existence of CEP.