Orateur
Description
We study the longitudinal spin transfer of $\Lambda$-hyperon production in semi-inclusive deep inelastic scattering with both current and target fragmentation mechanisms. For existing fixed-target experiments, such as JLab, COMPASS and HERMES, the events from the current region and those from the target fragmentation region are not clearly separated. However the study of target fragmentation is relatively limited, we propose a new approach to directly compute the target fracture functions based on the spectator diquark model, which can quantify the contributions of target fragmentation well. We find that the contribution from the target fragmentation can significantly suppress the spin transfer to the $\Lambda$ in the medium-energy SIDIS process. The predictions are consistent with existing experimental data from COMPASS, HERMES, and CLAS12, and will soon be examined at high energy levels in upcoming experiments.
