Vortical structure created in heavy ion collision leads to the polarization of hyperons phenomenon, which can be used as a probe to study the spin degree of freedom. RHIC Beam Energy Scan II program offers a good opportunity to study the hyperon polarization over the wide energy regime. In these proceedings, we report measurements of the global polarization of Λ, Λ̅, Ξ± and Ω± at √sNN = 7.7−27 GeV in Au+Au collisions from BES-II. The global hyperons polarization of all hyperons decrease as collision energy increases. Additionally, we report the second harmonics of local Λ, Λ̅ polarization and their difference at √sNN = 7.7−27 GeV, which can be used to probe the baryonic spin Hall effect. These measurements provide valuable insights into the spin dynamics within the QCD medium produced in heavy ion collisions.
Tan Lu (Fri,) studied this question.