Highlights from the STAR experiment

Joint Institute for Nuclear Research, Dubna, Russia

^* e-mail: aparin@jinr.ru

Published online: 3 April 2019

Abstract

We present an overview of the recent results obtained by the STAR Collaboration at RHIC.We report the beam energy dependence of directed flow of strange particles. These results support the assumption, that directed flow is formed before hadronization and observed particles are formed via coalescence of constituent quarks. First evidence of a non-zero directed flow of D⁰ meson is reported. We present the precision measurement of elliptic flow of D⁰ meson and the first measurement of Λ_c baryon in Au+Au collisions at $\sqrt{s_{NN}}=200\text{GeV}$, which suggests thermalization of charm quarks. We report results of global Λ polarization measurements in Au+Au collisions, together with the investigation of polarization dependence of centrality and transverse momentum p_T. Results from the STAR fixed-target program show good agreement with previously obtained results. A precise measurement of the ${}_{\text{Λ}}^{3}H$ lifetime is presented. Mesonic decay modes are used to reconstruct the ${}_{\text{Λ}}^{3}H$ from Au+Au collisions. The measured lifetime is about 50% shorter than the one of a free Λ, indicating a strong hyperon-nucleon interaction in the hypernucleus system. Finally, we give an outlook to detector upgrades for the Beam Energy Scan phase II.