Speaker
Description
Fluctuations of conserved charges are important probes to explore hot and dense medium in relativistic heavy-ion collisions. In this talk we focus on the experimentally-observed second-order cumulants of baryon number and electric charge at the top RHIC energy. We compare the ratio of these cumulants with the corresponding susceptibility ratio observed in lattice QCD numerical simulations. We show that, if one assumes that the experimental results on the cumulants are thermal, the "temperature" predicted from this comparison is significantly lower than that of the chemical freezeout. We argue that this discrepancy comes from the diffusion and resonance decays. The importance of the acceptance correction of the transverse-momentum cut is also emphasized.
