Theory of Spin Effects in Hard Hadronic Reactions

Abstract

I discuss the present situation with regard to a variety of theoretical topics in hadronic spin physics: (a) global analysis of the g1 data---positivity at leading and next-to-leading order, renormalisation-scheme dependence, parametrisation, and hyperon beta-decays; (b) items from the realm of transverse spin---twist-three effects, single-spin asymmetries, and transversity; and finally (c) recent developments in understanding the Q^2 evolution of orbital angular momentum.

Comments: 18 pages, 7 figures in eps files, packages used: autobf.sty, axodraw.sty