We report studies of charge-independent and charge-dependent two-particle differential number correlation functions, $R_2(\mathrm{\Delta }\eta ,\mathrm{\Delta }\phi )$, and transverse momentum correlation functions, $P_2(\mathrm{\Delta }\eta ,\mathrm{\Delta }\phi )$, of charged particles produced in Pb–Pb collisions at the LHC center-of-mass energy $\sqrt{s_{NN}}=$ 2.76 TeV with the UrQMD, AMPT, and EPOS models. Model calculations for $R_2$ and $P_2$ correlation functions are presented for inclusive charged hadrons ($h^{\pm }$) in selected transverse momentum ranges and with full azimuthal coverage in the pseudorapidity range $\left|\eta \right|<1.0$. We compare these calculations for the strength, shape, and particularly the width of the correlation functions with recent measurements of these observables by the ALICE collaboration. Our analysis indicates that comparative studies of $R_2$ and $P_2$ correlation functions provide valuable insight towards the understanding of particle production in Pb–Pb collisions. We find, in particular, that these models produce quantitatively different magnitudes and shapes for these correlation functions and none reproduce the results reported by the ALICE collaboration. Accounting for quantum number conservation in models, particularly charge conservation, is mandatory to reproduce the detailed measurements of number and transverse momentum correlation functions.

• Received 23 January 2020
• Revised 25 March 2021
• Accepted 24 November 2021

DOI:https://doi.org/10.1103/PhysRevC.104.064902