Spin-Flavor Decomposition in Polarized Semi-Inclusive Deep Inelastic Scattering Experiments at Jefferson Lab

Abstract

A Jefferson Lab experiment proposal was discussed in this talk. The experiment is designed to measure the beam-target double-spin asymmetries $A_{1n}^h$ in semi-inclusive deep-inelastic $\vec{n}(\vec{e},e^{\prime }{\pi }^{+})X$ and $\vec{n}(\vec{e},e^{\prime }{\pi }^{-})X$ reactions on a longitudinally polarized ${}^3$He target. In addition to $A_{1n}^h$, the flavor non-singlet combination $A_{1n}^{{\pi }^{+}-{\pi }^{-}}$, in which the gluons do not contribute, will be determined with high precision to extract $\Delta d_v(x)$ independent of the knowledge of the fragmentation functions. The data will also impose strong constraints on quark and gluon polarizations through a global NLO QCD fit.

arXiv comment5 pages, 4 figures, to appear in the proceedings of the First Workshop on Quark-Hadron Duality and the Transition to pQCD, Frascati, Italy. June 6-8, 2005