Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV in a multiphase transport model

TL;DR

This study uses the AMPT model to analyze Pb-Pb collisions at 2.76 TeV, successfully reproducing multiplicity and elliptic flow data from ALICE, and predicts detailed hadron spectra and flow patterns.

Contribution

It demonstrates that the AMPT model with standard parameters can accurately simulate key observables in high-energy heavy-ion collisions at the LHC.

Findings

Final charged particle multiplicity matches ALICE data with standard parameters.

Elliptic flow is consistent with ALICE data using a smaller parton scattering cross section.

Predicted spectra and flow of identified hadrons agree with experimental trends.

Abstract

The multiplicity and elliptic flow of charged particles produced in Pb-Pb collisions at center of mass energy $\sqrt{s_{NN}}=2.76$ TeV from the Large Hadron Collider are studied in a multiphase transport (AMPT) model. With the standard parameters in the HIJING model, which is used as initial conditions for subsequent partonic and hadronic scatterings in the AMPT model, the resulting multiplicity of final charged particles at mid-pseudorapidity is consistent with the experimental data measured by the ALICE Collaboration. This value is, however, increased by about 25% if the final-state partonic and hadronic scatterings are turned off. Because of final-state scatterings, particular those among partons, the final elliptic flow of charged hadrons is also consistent with the ALICE data if a smaller but more isotropic parton scattering cross section than previously used in the AMPT model for describing the charged hadron elliptic flow in heavy ion collisions at the Relativistic Heavy Ion Collider is used. The resulting transverse momentum spectra of charged particles as well as the centrality dependence of their multiplicity density and the elliptic flow are also in reasonable agreement with the ALICE data. Furthermore, the multiplicities, transverse momentum spectra and elliptic flows of identified hadrons such as protons, kaons and pions are predicted.