Spectra and elliptic flow of (multi-)strange hadrons at RHIC and LHC within viscous hydrodynamics+hadron cascade hybrid model

TL;DR

This study uses a hybrid viscous hydrodynamics and hadron cascade model to analyze spectra and elliptic flow of strange hadrons at RHIC and LHC, finding good overall agreement but noting areas for improvement.

Contribution

It applies the VISHNU hybrid model to describe spectra and flow of strange and multi-strange hadrons at RHIC and LHC energies, providing insights into mass ordering and model accuracy.

Findings

VISHNU describes spectra and elliptic flow well across centralities.

Mass ordering of elliptic flow among certain hadrons is reproduced.

Improvements needed for detailed mass ordering among p, Λ, and Ξ.

Abstract

Using the (2+1)-dimensional ultrarelativistic viscous hydrodynamics+hadron cascade, VISHNU, hybrid model, we study the $p_{\rm T}$-spectra and elliptic flow of $\Lambda$, $\Xi$, and $\Omega$ in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV and in Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV. Comparing our model results with the data measurements, we find that the VISHNU model gives general descriptions of the measurements of these strange and multi-strange hadrons at several centrality classes at RHIC and LHC. Mass ordering of elliptic flow $v_{2}$ among $\pi$, $K$, $p$, $\Lambda$, $\Xi$, and $\Omega$ are further investigated and discussed at the two collision systems. We find, at both RHIC and LHC, the $v_{2}$ mass ordering among $\pi$, $K$, $p$, and $\Omega$ are fairly reproduced within the VISHNU hybrid model, and more improvements are needed to implement for well describing the $v_{2}$ mass ordering among $p$, $\Lambda$, and $\Xi$.