Global Λ polarization in heavy-ion collisions from a transport model

Off-central relativistic heavy ion collisions impart very large orbital angular momenta onto the quark-gluon plasma, creating a strong vortex in the initial hot fluid and appearing eventually, via spin-vorticity coupling, as particle polarization. From the vorticity field given by a multi-phase transport model the authors compute the global polarization of Λ baryons which is in agreement with experimental data. This suggests that the spin of a hadron could provide information on quark-gluon plasma flow.