Phase diagram and baryon number fluctuations at finite temperature and magnetic field in a chiral model with screened interactions

In this paper, we study the effect of the dynamical screening of the four-quark interaction on the chiral phase transition and the baryon number fluctuations at finite temperature and magnetic field in an effective model inspired by QCD in the Coulomb gauge. The screening leads to a medium-dependent coupling that generates inverse magnetic catalysis at finite magnetic field. We observe the decreasing temperature of the chiral crossover, in agreement with lattice QCD predictions, and find a critical point for large magnetic fields. We also observe a strong enhancement of the baryon number fluctuations in the vicinity of the crossover.