Two-component source to explain $\Lambda$ and $\bar{\Lambda }$ global polarization in non-central heavy-ion collisions

Abstract

The STAR Beam Energy Scan program has found a difference in the global polarization of $\Lambda$s and $\bar{\Lambda }$s produced in $Au+Au$ collisions. This difference is larger for lower center of mass collision energies. In this work we show that a two-component source, consisting of a high density core and a lower density corona, can describe quantitatively the $\Lambda$ and $\bar{\Lambda }$ polarization as a function of collision energy.

8 pages, 7 figures