Hyperon polarization in deep inelastic scattering

Abstract

We have implemented the recent extension of the string+${}^3P_0$ model of spin-dependent hadronization that includes the production of spin-$1/2$ baryons in the Pythia event generator for the simulation of deep inelastic scattering (DIS). The implementation in Pythia is performed by extending the StringSpinner package, which is then used to study the spontaneous polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons produced in the current and target fragmentation regions in DIS with an unpolarized proton target. We find a large spontaneous polarization for $\Lambda$s in the target fragmentation region, calling for the measurement of such observable that can shed light on the quark spin dependence of hadronization.