Abstract

We present the first measurement of the proton-Omega correlation function in heavy-ion collisions for the central (0-40%) and peripheral (40-80%) Au + Au collisions at root s(NN) = 200 GeV by the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). Predictions for the ratio of peripheral collisions to central collisions for the proton-Omega correlation function are sensitive to the presence of a nucleon-Omega bound state. These predictions are based on the proton-Omega interaction extracted from (2 + 1)-flavor lattice QCD calculations at the physical point. The measured ratio of the proton-Omega correlation function between the peripheral (small system) and central (large system) collisions is less than unity for relative momentum smaller than 40 MeV/c. Comparison of our measured correlation ratio with theoretical calculation slightly favors a proton-Omega bound system with a binding energy of similar to 27 MeV. (C) 2019 Published by Elsevier B.V.