Inclusive Charged-Particle Kinematic Distributions at LHC Energies: Data versus Theory

Abstract

The transverse momentum distributions of inclusive charged particles in pseudorapidity bins with a width of 0.2 are reported for a simulation study of PYTHIA8, Sibyll, and EPOS. The models’ predictions are compared with the experimental measurements reported by the CMS experiment in symmetric pp collisions, allowing the maximum energy for new particle production at s = 0.9, 2.36, and 7 TeV. While comparing the models’ predictions with the data, we found that the default module of the PYTHIA model reproduced a good prediction of the data because it tuned the lower cut-off phase space parameter of the transverse momentum. In the second place, the EPOS model reproduced predictions that were close to the data, while the Sibyll model reproduced the data in a narrow region of the pT distributions. In addition to that, the fit of the pT distribution of the data by the standard distribution function was used to obtain the effective temperature of the hadronic medium. The effective temperature increased with an increase in the pseudorapidity and had a more significant value at higher center-of-mass energies, which may indicate a change in the reaction mechanism or possible formation of a different phase of hadronic matter.

Keywords

• effective temperature
• transverse momentum distributions
• pseudorapidity dependence
• LHC energies