The Proton-$\Omega$ correlation function in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV

TL;DR

This study measures the proton-$ ext{Omega}$ correlation function in Au+Au collisions at 200 GeV, providing insights into possible bound states and the nature of the proton-$ ext{Omega}$ interaction.

Contribution

First measurement of the proton-$ ext{Omega}$ correlation function in heavy-ion collisions, testing predictions of bound states from lattice QCD calculations.

Findings

Correlation ratio less than unity at low relative momentum.

Data slightly favors a proton-$ ext{Omega}$ bound state with ~27 MeV binding energy.

Results inform understanding of nucleon-$ ext{Omega}$} interactions.

Abstract

We present the first measurement of the proton-$\Omega$ correlation function in heavy-ion collisions for central (0-40$\%$) and peripheral (40-80$\%$) Au+Au collisions at \sqrtsNN\,\,=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 proton-$\Omega$ correlation function from peripheral (small system) to central (large system) collisions is less than unity for relative momentum smaller than 40 MeV/c. Comparison of our measured correlation ratio with the theoretical calculation slightly favors a proton-$\Omega$ bound system with a binding energy of $\sim$ 27~MeV.