Global polarization measurement in Au+Au collisions

Understand

The system created in non-central relativistic nucleus-nucleus collisions possesses large orbital angular momentum.

• Due to 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 Lambda and anti-Lambda hyperon global polarization measurements in Au+Au collisions at sqrt{s_NN}=62.4 GeV and 200 GeV performed with the STAR detector at RHIC.
• The observed global polarization of Lambda and anti-Lambda hyperons in the STAR acceptance is consistent with zero within the precision of the measurements.