Global spin polarization of multistrange hyperons and feed-down effect in heavy-ion collisions

Global spin polarization of hyperons is an important observable to probe the vorticity of the quark-gluon plasma produced in heavy-ion collisions. We calculate the global polarizations of Lambda, Xi(-), and Omega(-) in Au+Au collisions at energies root s(NN) = 7.7-200 GeV based on a multiphase transport model. Our calculations suggest that their primary global polarizations fulfill P Omega- similar or equal to 5/3P(Xi-) similar or equal to 5/3P(Lambda). We also estimate the feed-down effect of particle decay on the global polarization. With the feed-down effect taken into account, the global polarizations of Lambda and Xi(-) are clearly separated, and the final global polarizations are in the ordering: P Omega- > P Xi- > P-Lambda. Such a relation can be tested in experiments, which will provide us more information about the global polarization mechanism. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).