Strangeness Enhancement at LHC Energies Using the Thermal Model and EPOSLHC Event Generator

Mahmoud Hanafy,Asmaa G Shalaby,Omnia S A Qandil,Roelof Bijker

doi:10.1155/2021/2489232

Mahmoud Hanafy, Asmaa G Shalaby + Show 2 more

Open Access

https://doi.org/10.1155/2021/2489232

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Abstract

The strangeness enhancement signature of QGP formation at LHC energies is carefully tackled in the present study. Based on HRG, the particle ratios of mainly strange and multistrange particles are studied at energies from lower s ~ 0.001 up to 13 TeV. The strangeness enhancement clearly appeared at more high energies, and the ratios are confronted to the available experimental data. The particle ratios are also studied using the Cosmic Ray Monte Carlo (CRMC) interface model with its two different event generators, namely, EPOS 1.99 and EPOSlhc, which show a good agreement with the model calculations at the whole range of the energy. We utilize them to produce some particles ratios. EPOS 1.99 is used to estimate particle ratios at lower energies from AGS up to the Relativistic Heavy Ion Collider (RHIC) while EPOSlhc is used at LHC energies. The production of kaons and lambda particles is studied in terms of the mean multiplicity in p-p collisions at energies ranging from 4 to 26 GeV. We find that both HRG model and the used event generators, EPOS 1.99 and EPOSlhc, can describe the particle ratios very well. Additionally, the freeze-out parameters are estimated for different collision systems, such as p-p and Pb-Pb, at LHC energies using both models.

Highlights

One of the most important signatures of the phase transition between the hadronic matter “confined phase” to the quarkgluon plasma (QGP) “deconfined phase” is the strangeness enhancement, in other words, the production of strange particles [1]
The strangeness enhancement is combined with gluon existence in QGP, in which the gluon dissolves to a pair of strange quarks rapidly [2]
For some suggested strange and multistrange particles, there is a lack of experimental data; we used two different generators, i.e., EPOS 1.99 and EPOSlhc, to predict their results

Summary

Introduction

One of the most important signatures of the phase transition between the hadronic matter “confined phase” to the quarkgluon plasma (QGP) “deconfined phase” is the strangeness enhancement, in other words, the production of strange particles [1]. The main target of the present work is to investigate the strangeness enhancement in terms of various particle ratios such as k+/π+, k−/π−, π−/π+, k−/k+, p/π−, Λ/π−, Λ /Λ, Ω /Ω, and Ξ+/Ξ− and strange and multistrange particles such as φð1020Þ/k0s ∗ð892Þ, Σ∗+8/Σ∗+8, Σ∗08/Σ∗08, Σ∗−8/Σ∗−8, Ξ∗08/ Ξ∗08, and Ξ∗−8/Ξ∗−8 from low to high energies using different models, namely, HRG, EPOS 1:99, and EPOSlhc. Both event generators, EPOS 1:99 and EPOSlhc, are executed through the CRMC interface model to produce the abovementioned particles for an ensemble of 100,000 events where the fusion option is turned on.

Formalism

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Results and Discussion

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Conclusion