Bulk Properties of the System Formed in Au+Au Collisions at $\sqrt{s_{\mathrm{NN}}}$ = 14.5 GeV

Abstract

We report systematic measurements of bulk properties of the system created in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 14.5 GeV recorded by the STAR detector at the Relativistic Heavy Ion Collider (RHIC).The transverse momentum spectra of $\ddot{I}{€}^{\pm }$, $K^{\pm }$ and $p(\bar{p})$ are studied at mid-rapidity ($|y|<0.1$) for nine centrality intervals. The centrality, transverse momentum ($p_T$),and pseudorapidity ($\hat{I}\cdot$) dependence of inclusive charged particle elliptic flow ($v_2$), and rapidity-odd charged particles directed flow ($v_1$) results near mid-rapidity are also presented. These measurements are compared with the published results from Au+Au collisions at other energies, and from Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV. The results at $\sqrt{s_{\mathrm{NN}}}$ = 14.5 GeV show similar behavior as established at other energies and fit well in the energy dependence trend. These results are important as the 14.5 GeV energy fills the gap in $\hat{I}{¼}_B$, which is of the order of 100 MeV,between $\sqrt{s_{\mathrm{NN}}}$ =11.5 and 19.6 GeV. Comparisons of the data with UrQMD and AMPT models show poor agreement in general.

30 pages, 29 figures and 8 tables