Abstract
The system created in noncentral relativistic nucleus-nucleus collisions possesses large orbital angular momentum. Because of spin-orbit coupling, particles produced in such a system could become globally polarized along the direction of the system angular momentum. We present the results of Λ and Λ̄ hyperon global polarization measurements in Au+Au collisions at sNN=62.4 and 200 GeV performed with the STAR detector at the BNL Relativistic Heavy Ion Collider (RHIC). The observed global polarization of Λ and Λ̄ hyperons in the STAR acceptance is consistent with zero within the precision of the measurements. The obtained upper limit, |PΛ,Λ̄|≤0.02, is compared with the theoretical values discussed recently in the literature.