Azimuthal Anisotropy from STAR Experiment

TL;DR

This paper reports measurements of azimuthal anisotropy coefficients in gold-gold and uranium-uranium collisions at RHIC, providing data crucial for understanding the initial conditions and medium properties in heavy ion collisions.

Contribution

It presents detailed measurements of harmonic coefficients $v_{n}$ up to fifth order as functions of transverse momentum and centrality, including ultra-central U+U collisions, offering new constraints for theoretical models.

Findings

Measured $v_{n}$ coefficients for $n=1$ to 5 in Au+Au and U+U collisions.

Provided $v_{n}$ data as functions of $p_{T}$ and centrality.

Presented $v_{n}$ results in ultra-central U+U collisions.

Abstract

We report the measurement of first (\textit{n} = 1) and higher order(\textit{n} = 2-5) harmonic coefficients ($v_{n}$) of the azimuthal anisotropy in the distribution of the particles produced in Au+Au collisions at $\sqrt{s_{NN}}$ =200 GeV and U+U collisions at $\sqrt{s_{NN}}$ =193 GeV, recorded with the STAR detector at RHIC. The differential measurement of $(v_{n})$ is presented as a function of transverse momentum ($p_{T}$) and centrality. We also present $v_{n}$ measurement in the ultra-central collisions in U+U collisions. These data may provide strong constraints on the theoretical models of the initial condition in heavy ion collisions and the transport properties of the produced medium.