Abstract

We compute the Lambda and (Lambda) over bar global polarization in semi-central heavy-ion collisions modeling the source as consisting of a high-density core and a less dense corona. We show that when more Lambda s than (Lambda) over bars are produced in the corona, and this is combined with a smaller number of Lambda s coming from the core, as compared to those coming from the corona, an amplification effect for the (Lambda) over bar with respect to that of Lambda polarization can occur. This amplification becomes more important for lower collision energies and quantitatively accounts for the Lambda and (Lambda) over bar polarizations measured by the STAR beam energy scan. (C) 2020 The Authors. Published by Elsevier B.V.