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arXiv · 1312.3820

Production and ratio of $π$, K, p and $Λ$ in Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

S. Zhang·L. X. Han·Y. G. Ma·J. H. Chen·C. Zhong
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Abstract

The particle production and their ratios for $π$, $K$, $p$, and $Λ$ are studied in Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV based on a blast-wave model with thermal equilibrium mechanism. The transverse momentum spectra of the above mentioned particles at the kinetic freeze-out stage are discussed. The modification of the inverse slope of pion transverse momentum spectrum due to resonance decay has also been investigated. In addition, we found that the anti-particles to particles ratio as well as kaons to pions ratio agree with the data by the LHC-ALICE Collaboration reasonably well, while the $p/π$ ratio is overestimated by a factor of 1.5, similar to those from other thermal model calculations. It is found that the ratios of $p/π$ and $K/π$ are dominated by the radial flow but slightly affected by the baryon chemical potential. Our study thus constrains the parameters at the chemical and kinetic freeze-out stages within the framework of thermal model in Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV, and will help better understand the properties of the dense and hot matter created in high-energy heavy-ion collisions at freeze-out stage.

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S. Zhang, L. X. Han, Y. G. Ma, J. H. Chen, C. Zhong. 2014-02-13. Production and ratio of $π$, K, p and $Λ$ in Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV. https://doi.org/10.1103/physrevc.89.034918

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