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arXiv · 1808.04053

Extracting strange quark freeze-out information in Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV from $ϕ$ and $Ω$ production

Jie Pu·Kai-Jia Sun·Lie-Wen Chen
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Abstract

Using a covariant quark coalescence model combined with a blast-wave-like analytical parametrization for (anti-)strange quark phase-space freeze-out configuration, we extract information on strange quark freeze-out dynamics in Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV by fitting the measured transverse momentum spectra and elliptic flows ($v_2$) of $ϕ$ mesons and $Ω$ baryons. We find that although both the measured and calculated $v_2$ of $ϕ$ and $Ω$ satisfy the number-of-constituent-quark (NCQ) scaling, the NCQ-scaled $v_2$ is significantly smaller than the $v_2$ of strange quarks, implying that the NCQ-scaled $v_2$ of $ϕ$ and $Ω$ cannot be simply identified as the $v_2$ of strange quarks at hadronization. Meanwhile, our results indicate that the covariant quark coalescence model can nicely describe the spectra and elliptic flows of $ϕ$ and $Ω$ simultaneously, suggesting the coalescence mechanism is still valid for $ϕ$ and $Ω$ production in Pb+Pb collisions at LHC energies.

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Jie Pu, Kai-Jia Sun, Lie-Wen Chen. 2018-12-04. Extracting strange quark freeze-out information in Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV from $ϕ$ and $Ω$ production. https://doi.org/10.1103/physrevc.98.064905

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