Vorticity in the QGP liquid and hyperon polarization at the RHIC BES energies
We calculate the polarization of hyperons in Au-Au collisions at RHIC Beam Energy Scan range = 7.7, ..., 200 GeV in a state-of-the-art 3+1 dimensional cascade + viscous hydro model vHLLE+UrQMD. We find that the polarization of in the out-of-plane direction decreases substantially with collision energy. We explore the connection between the polarization signal and thermal vorticity and discuss the feed-down and hadronic rescattering effects on the mean polarization of all produced Λ hyperons.