Measurements of the Elliptic and Triangular Azimuthal Anisotropies in Central $^{3}\mathrm{He}+\mathrm{Au}$, $d+\mathrm{Au}$ and $p+\mathrm{Au}$ Collisions at $\sqrt{{s}_{NN}}=200\text{ }\text{ }\mathrm{GeV}$

Measurements of the Elliptic and Triangular Azimuthal Anisotropies in Central ${}^{3}{He} + Au$ , $d + Au$ and $p + Au$ Collisions at $\sqrt{s_{N N}} = 200 GeV$

M. I. Abdulhamid et al. (STAR Collaboration)

Phys. Rev. Lett. 130, 242301 – Published 15 June 2023

Abstract

The elliptic ( $v_{2}$ ) and triangular ( $v_{3}$ ) azimuthal anisotropy coefficients in central ${}^{3}{He} + Au$ , $d + Au$ , and $p + Au$ collisions at $\sqrt{s_{NN}} = 200 GeV$ are measured as a function of transverse momentum ( $p_{T}$ ) at midrapidity ( $| η | < 0.9$ ), via the azimuthal angular correlation between two particles both at $| η | < 0.9$ . While the $v_{2} (p_{T})$ values depend on the colliding systems, the $v_{3} (p_{T})$ values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.