Investigating the quark flavor dependence of the chiral magnetic effect with a multiphase transport model

Because the properties of the QCD phase transition and the chiral magnetic effect (CME) depend on the number of quark flavors ($N_f$) and quark mass, relativistic heavy-ion collisions provide a natural environment to investigate the flavor features if quark deconfinement occurs. We introduce an initial two-flavor or three-flavor dipole charge separation into a multiphase transport (AMPT) model to investigate the flavor dependence of the CME. By taking advantage of the recent ALICE data of charge azimuthal correlations with identified hadrons, we attempt to disentangle two-flavor and three-flavor CME scenarios in Pb+Pb collisions at 2.76 TeV. We find that the experimental data show a certain potential to distinguish the two scenarios, therefore we further suggest to collect more data to clarify the possible flavor dependence in future experiments.

Figure 1

The impact parameter $b$ dependences of magnetic field $B_y$ (see right $y$ axis, dot-dash) and initial charge separation percentages (see left $y$ axis) for two-flavor CME (dash) and three-flavor CME (solid) in Pb+Pb collisions at 2.76 TeV. The magnetic field $B_y$ is taken from Ref. [8].

Figure 2

The centrality dependence of charge-particle azimuthal correlation $\gamma$ in Pb+Pb collisions at 2.76 TeV, where the experimental data are taken from Ref. [14].

Figure 3

The $p_T$ dependence of hadron-hadron charge azimuthal correlation in Pb+Pb collisions (30–50%) at 2.76 TeV, where two bands represent the ALICE data [24].

Figure 4

Same as Fig. 3 but for kaon-hadron charge azimuthal correlation.