Λ0 polarization as a probe for production of deconfined matter in ultrarelativistic heavy-ion collisions -: art. no. 024902

We study the polarization change of Lambda(0)'s produced in ultra-relativistic heavy-ion collisions with respect to the polarization observed in proton-proton collisions as a signal for the formation of a quark-gluon plasma (QGP), Assuming that, when the density of participants in the collision is larger than the critical density for QGP formation, the Lambda(0) production mechanism changes from recombination type processes to the coalescence of free valence quarks, we find that the Lambda(0) polarization depends on the relative contribution of each process to the total number of Lambda(0)'s produced in the collision. To describe the polarization of Lambda(0)'s in nuclear collisions for densities below the critical density for the QGP formation, we use the DeGrand-Miettinen model corrected for the effects introduced by multiple scattering of the produced Lambda(0) within the nuclear environment.