Charge fluctuations in Au+Au collisions at RHIC energy

Abstract

A hadron and string cascade model, JPCIAE, together with the corresponding Monte Carlo event generator, has been employed in this paper to investigate further the charge fluctuations in Au+Au collisions at √ s nn = 130 GeV. The default JPCIAE calculations are in good agreement with PHENIX and STAR data. We found that the thermal predictions for the π gas, the resonance π gas and quark matter deviate, respectively. from the corresponding dynamical simulations from the JPCIAE model. The discrepancies were also found between the π charge fluctuations and the charge fluctuations of all species of hadrons. However the charge fluctuations for “π from ρ and ω decay” and for all the hadrons from resonance decay are close to each other, indicating the correlation between positively and negatively charged hardrons is not sensitive to the species of hardrons. This work shows further that it is questionable to use the charge fluctuations as a signature of QGP.