Azimuthal anisotropy measurements of strange and multistrange hadrons in U+U collisions at $\sqrt{s_{NN}}=193$ GeV at the BNL Relativistic Heavy Ion Collider

Abstract

We present systematic measurements of azimuthal anisotropy for strange and multistrange hadrons ($K_s^0$, $\hat{I}›$, $\hat{I}ž$, and $\hat{I}\text{c◯}$) and $\ddot{I}•$ mesons at midrapidity ($|y|<$ 1.0) in collisions of U + U nuclei at $\sqrt{s_{NN}}=193$ GeV, recorded by the STAR detector at the Relativistic Heavy Ion Collider. Transverse momentum ($p_{\text{T}}$) dependence of flow coefficients ($v_2$, $v_3$, and $v_4$) is presented for minimum bias collisions and three different centrality intervals. Number of constituent quark scaling of the measured flow coefficients in U + U collisions is discussed. We also present the ratio of $v_n$ scaled by the participant eccentricity (${\epsilon }_n\left\{2\right\}$) to explore system size dependence and collectivity in U + U collisions. The magnitude of $v_2/{\epsilon }_2$ is found to be smaller in U + U collisions than that in central Au + Au collisions contradicting naive eccentricity scaling. Furthermore, the ratios between various flow harmonics ($v_3/v_2^{3/2}$, $v_4/v_2^{4/2}$) are studied and compared with hydrodynamic and transport model calculations.

22 pages, 16 figures