Anisotropic flows of light-flavor and charmed hadrons in Pb+Pb collisions at LHC energy

TL;DR

This paper uses a constituent quark equal-velocity combination model to analyze and predict the anisotropic flow of light-flavor and charmed hadrons in Pb+Pb collisions at LHC energies, explaining experimental data and providing new flow predictions.

Contribution

The study introduces the EVC model to describe hadron flows based on quark flows, successfully explaining existing data and predicting flows of various charmed hadrons at LHC energies.

Findings

Experimental data for $v_2$ and $v_3$ of light-flavor hadrons are well explained by the EVC model.

Additional two-kaon coalescence is needed to explain $$ meson data at 5.02 TeV, indicating hadronic rescattering effects.

Predicted anisotropic flows of charmed hadrons match preliminary experimental data.

Abstract

We apply a constituent quark equal-velocity combination (EVC) model to study the elliptic flow ($v_{2}$) and triangular flow ($v_{3}$) of light-flavor and single-charmed hadrons in Pb+Pb collisions at $\sqrt{s_{NN}}=$ 2.76 and 5.02 TeV. $v_{2,3}$ of hadrons in the EVC model can be expressed as a linear superposition of the $v_{2,3}$ of quarks at the same velocity as that of the hadrons. We find that available experimental data for $v_{2}$ and $v_{3}$ of $p$, $\Lambda$, $\Xi$, and $\Omega$ as the function of transverse momentum ($p_{T}$) can be consistently explained by the EVC formula using a $v_{2}$ of up/down quarks and a $v_{2}$ of strange quarks. In comparison with $v_{2}$ data of $\phi$ at $\sqrt{s_{NN}}=$2.76 TeV which can be naturally explained by $v_{2}$ of strange quarks, explanation of data of $\phi$ mesons at $\sqrt{s_{NN}}=$5.02 TeV requires an additional contribution of two-kaon coalescence, which indicates approximately 20% influence of final-state hadronic rescattering on $v_{2}$ of $\phi$ at $\sqrt{s_{NN}}=$5.02 TeV. Using $v_{2}$ and $v_{3}$ of light-flavor quarks obtained in studying light-flavor hadrons and $v_{2}$ and $v_{3}$ of charm quarks determined from $D^{0}$ meson data, we apply the EVC model to predict the anisotropic flows of $D_{s}^{+}$, $\Lambda_{c}^{+}$, $\Xi_{c}^{0}$, and $\Omega_{c}^{0}$ and compare them with the available experimental data. The preliminary data for $v_{2}$ of $D^{0}$, $D_{s}^{+}$, and $\Lambda_{c}^{+}$ at $\sqrt{s_{NN}}=$ 5.36 TeV are found to be naturally described by the EVC model.