Measurements of elliptic and triangular flow in high-multiplicity 3He + Au collisions at [formula omitted

Abstract

In this paper, we present measurements of two-particles correlations across a rapidity gap of about |Δη|>3.5 in central 3He+Au and p+p collisions at sNN=200 GeV. A near-side peak is observed for central 3He+Au collisions while not for p+p. We also present the first measurements of elliptic v2 and triangular v3 anisotropy coefficients with respect to their corresponding event planes. The measured v2 and v3 are compared with that in Au+Au, p+Au, d+Au collisions at same collision energy, and several models calculations. The comparison indicates that the initial geometry with final state interactions play important role for the developing of anisotropy in the small collisions systems such as p/d/3He+Au collisions. We also present measurements of v2 for identified π±, K± and (anti)protons in central 3He+Au collisions, and quark-number scaling is observed which is similar to that seen in A+A heavy ion collisions.