2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/47911We discuss polarized parton distributions and their effects on spin asymmetries at RHIC. In particular, transversity distributions and transverse spin asymmetry are studied. First, we show the $Q^2$ evolution difference between a transversity distribution and a corresponding longitudinally polarized distribution. The difference could be an important test of perturbative QCD in high-energy spin physics. Then, the transverse spin asymmetry $A_{TT}$ is calculated with possible transversity distributions. Next, we study antiquark flavor asymmetry $Δ_{_T} \bar u/ Δ_{_T} \bar d$ in the transversity distributions by using a simple model. Its effects on the transverse spin asymmetry are also discussed.1+5 pages, LATEX with epsfig.sty, wrapfig.sty, and sprocl.sty, 3 eps figures. Talk given at the 6th International Workshop on Deep Inelastic Scattering and QCD. Brussels, Belgium, April 4-8, 1998, to be published in proceedings by the World Scientific. Complete postscript file including the figures is available at http://www.cc.saga-u.ac.jp/saga-u/riko/physics/quantum1/structure.html Email: 97sm16@edu.cc.saga-u.ac.jp, 98td25@edu.cc.saga-u.ac.jp, kumanos@cc.saga-u.ac.jp, 96td25@edu.cc.saga-u.ac.jpHigh Energy Physics - PhenomenologyHigh Energy Physics - ExperimentNuclear Theorytext