Seminar “Nuclear Theory”

Date and Time: Monday, 24 May 2021, at 3:30 PM

Venue: Online conference on Zoom, Bogoliubov Laboratory of Theoretical Physics

Seminar topic: “Phase diagram and standard particles in the SU(3) NJL-like models”

Speaker: A. V. Friesen

Abstract:

Starting from the NJL model with Polyakov loop we consider the composite particles we managed to build with the u, d, s quarks. We start from the light pseudoscalar mesons and study how they behave with increasing temperature and baryonic density. We compare the pole approximation (Breit-Wigner) with the Beth-Uhlenbeck approach in description of the bounding state. And we evaluate the K/π ratio near the phase transition in the hadronic matter. A sharp “horn” effect in the K⁺/π⁺ ratio is explained by the enhanced pion production which can be described by the occurrence of a nonequilibrium pion chemical potential of the order of the pion mass. We elucidate that the horn effect is not related to the existence of a critical endpoint in the QCD phase diagram. We briefly discuss the diquark properties and baryon modelling in the NJL like models.