Particle Production at RHIC and LHC Energies

A. Tawfik; E. Gamal; A. G. Shalaby

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arXiv · 1209.5379

Particle Production at RHIC and LHC Energies

A. Tawfik·E. Gamal·A. G. Shalaby

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Abstract

The production of different particle species is recently measured in $Pb-Pb$ collisions by the ALICE experiment at $\sqrt{s}=7 $TeV. This motivates the use of various bosons and baryons measured at lower center-of-mass energies in comparing their ratios to the hadron resonance (HRG) gas model and PYTHIA event generator. It is found that the particle-to-antiparticle ratios are perfectly reproduce by means of HRG and PYTHIA at RHIC and LHC energies. The kaon-to-pion and proton-to-pion ratios are entirely overestimated by the HRG model. The PYTHIA event generator obviously underestimates the kaon-to-pion ratio and simultaneously reproduces the proton-to-pion ratio, almost perfectly, especially at LHC energy. While matter-to-antimatter and non-strange abundances are partly in line with predictions from the HRG model, it is found in the ALICE experiment that the measured baryon ratios are suppressed by a factor of $\sim1.5$. The strange abundances are overestimated in the HRG model.

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A. Tawfik, E. Gamal, A. G. Shalaby. 2012-09-24. Particle Production at RHIC and LHC Energies. https://arxiv.org/abs/1209.5379

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