Transversity distributions and spin asymmetries

الأصل · EN

We discuss transversity distributions and transverse spin asymmetries. First, Q² evolution results are shown for transversity and longitudinally polarized distributions. Second, the antiquark flavor asymmetry Δₜ u/Δₜ d is discussed in two different descriptions, a meson-cloud model and an exclusion model. Both calculations produce a significant Δₜ d excess over Δₜ u. Third, we explain general formalism of the polarized proton-deuteron Drell-Yan processes. This study is partly intended to find the asymmetry Δₜ u/Δₜ d by the p-d asymmetry. However, the existence of tensor structure in the deuteron produces a number of new structure functions. There exist 108 structure functions and 22 ones even after integrating the cross section over the virtual-photon transverse momentum Qₜ.