Speaker
Description
Vector meson (VM) production in polarized quark fragmentations has been recently studied in the context of the string+${}^3P_0$ model of hadronization. The spin effects for the production of VMs depend on the coupling of the mesons to the quarks in the fragmentation chain, which is parametrized in terms of two free parameters. One of the parameters governs the fraction of longitudinally polarized VMs produced in the fragmentation process, while the other governs the oblique polarization of VMs and is a source of Collins effect. Focusing on Collins transverse spin asymmetries in SIDIS, and using the Monte Carlo implementation of the string+${}^3P_0$ model in the Pythia event generator, we show that the contribution of VM production and decay to the measured asymmetries is large and is relevant for the interpretation of the available asymmetry data. Predictions for the Collins TSA for inclusive production of $\rho$ and K* mesons in SIDIS, a poorly measured observable but relevant for a deeper insight on the spin-dependence of the fragmentation process, at future facilities such as JLAB22 are also discussed.
