Spin polarization dynamics in the non-boost-invariant background
Wojciech Florkowski, Radosław Ryblewski, Rajeev Singh, Gabriel Sophys
Abstract
Space-time evolution of spin polarization within the framework of hydrodynamics with spin based on de Groot---van Leeuwen---van Weert forms of energy-momentum and spin tensors is studied. Due to the nonboost invariant flow in the system the spin polarization components couple to each other implying some effects on the spin polarization observables. We study transverse-momentum and rapidity dependence of mean spin polarization vector for $\mathrm{\ensuremath{\Lambda}}$ hyperons. Our results show qualitative agreement for rapidity dependence of the global spin polarization with the experiments and other models. The quadrupole structure of the longitudinal component at midrapidity is not found; however, as compared to the results for Bjorken expansion, some nontrivial signal at forward rapidities is observed.