Longitudinal $\bar{\Lambda}_0$ polarization in heavy-ion collisions as a probe for QGP formation

We present an analysis of the longitudinal \(\bar{\Lambda}_0\) polarization in ultrarelativistic heavy-ion collisions. The polarization of \(\bar{\Lambda}_0\)’s coming from the decay chain \(\bar{\Xi}\rightarrow \bar{\Lambda}_0 + \pi\) exhibits a very well differentiated behavior depending on the production region of the primordial \(\bar{\Xi}\)’s. This effect reflects the different values of the \(N_{\bar{\Xi}}/N_{\bar{\Lambda}_0}\) ratio in the QGP region, where nucleon-nucleon interactions take place in a hot and dense environment, and the peripherical region, in which ordinary nucleon-nucleon interactions occur. An increase in the longitudinal \(\bar{\Lambda}_0\) polarization signals a strangeness enhancement which is thought of as a property of the QGP phase.