Speaker
Description
Event-by-event fluctuations of conserved quantities such as electric charge, baryon number and strangeness in ultrarelativistic heavy-ion collisions provide insight into the properties of the quark-gluon plasma and the QCD phase diagram. The net-charge fluctuations in finite phase space are usually studied using the $\nu_{dyn}$ observable, which is robust against the detection efficiency losses and with a proper multiplicity scaling it becomes equivalent to the strongly intensive quantity $\Sigma$. In this talk, the values of $\nu_{dyn}$ are explored with ALICE detector in various colliding systems, namely, pp and p-Pb at $\sqrt{s_{\rm NN}} = 5.02$ TeV, Pb-Pb at $\sqrt{s_{\rm NN}} = 2.76$ and 5.02 TeV, and Xe-Xe at $\sqrt{s_{\rm NN}} = 5.44$ TeV. The observed dependence of $\nu_{dyn}$ on charged-particle density shows a regular smooth evolution of net-charge fluctuations from smaller to larger collision systems. Furthermore, the observed negative values of $\nu_{dyn}$ indicate the dominance of correlation between the oppositely charged particle pairs as compared to those arising from the like-sign charge pairs. These findings are compared to the predictions of HIJING, EPOS and PYTHIA models. Effect of the kinematical acceptance has also been investigated by examining the $\nu_{dyn}$ dependence on the width of the pseudorapidity window within the ALICE acceptance $|\eta|<0.8$ and in different transverse momentum ranges, whereas the effect of the hadronic resonance decays is studied by comparing the experimental findings with the prediction of HIJING model.
| First author | ALICE CC chairs |
|---|---|
| alice-cc-chairs@cern.ch | |
| Collaboration / Activity | ALICE |
