2025/04/20 by Mao, Shijun
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.2504.14532
The correlations χBQ11, χBS11 , χQS11 and quadratic (quartic) fluctuations χB, Q, S2,4 of baryon number B, electric charge Q and strangeness S are investigated in a three-flavor PNJL model at finite temperature and magnetic field. The inverse magnetic catalysis (IMC) effect is introduced through the magnetic field dependent parameters G(eB) or T0(eB), and we make comparison of the results in the cases with and without IMC effect. Since including IMC effect does not change the strength of phase transition under external magnetic field, it does not lead to qualitative difference in the correlations and fluctuations, but modifies their values. Under vanishing and nonvanishing magnetic field, the correlations and fluctuations increase with temperature, and then show the peak around the pseudocritical temperatures of chiral restoration and deconfinement phase transitions. The peak structure in χBQ11, χB4 and χQ4 are much more apparent than in others. The correlations and fluctuations along the phase transition line under external magnetic field are characterized by the scaled correlations χ11XY=\fracχ11XY(eB,Tpcc(eB))χ11XY(eB=0,Tpcc(eB=0)) and scaled quadratic (quartic) fluctuations χ2,4X=\fracχ2,4X(eB,Tpcc(eB))χ2,4X(eB=0,Tpcc(eB=0)), with X, Y=B, Q, S and X ≠ Y at the pseudocritical temperature Tpcc of chiral restoration phase transition. They increase with magnetic fields due to the increase of phase transition strength under magnetic fields. Among them, χ11BQ increases fastest, which may serve as the magnetometer of QCD.