The elliptic flow of multi-strange hadrons in $\sqrt{s_{NN}}$ = 200 GeV Au + Au collisions at STAR

TL;DR

This paper reports measurements of elliptic flow ($v_{2}$) for multi-strange hadrons in 200 GeV Au+Au collisions, revealing collective behavior and potential mass ordering breaking, shedding light on the properties of the quark-gluon plasma.

Contribution

First measurement of $v_{2}$ for multi-strange hadrons at RHIC, demonstrating partonic collectivity and exploring mass ordering effects.

Findings

Multi-strange hadrons exhibit significant elliptic flow similar to other hadrons.

Results support the presence of partonic collectivity in the created medium.

Possible breaking of mass ordering for $\,phi$ mesons at low $p_{T}$.

Abstract

The measurement of the elliptic flow, $v_{2}$, provides a powerful tool for studying the properties of hot and dense medium created in high-energy nuclear collisions. We present the measurement of $v_{2}$ of multi-strange hadrons ($\phi$, $\Xi$ and $\Omega$) in $\sqrt{s_{NN}}$= 200 GeV Au + Au collisions at STAR. In minimum-bias Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV, a significant amount of elliptic flow, almost identical to other mesons and baryons, is observed for multi-strange hadrons. Experimental observations of $p_{T}$ dependence of $v_{2}$ of identified particles at RHIC support partonic collectivity. We also discuss the possible breaking of mass ordering of the $\phi$ mesons in the low $p_{T}$ region.