Determination of polarized parton distribution functions

Abstract

We study parametrization of polarized parton distribution functions in the \alpha_s leading order (LO) and in the next-to-leading order (NLO). From \chi^2 fitting to the experimental data on A_1, optimum polarized distribution functions are determined. The quark spin content \Delta\Sigma is very sensitive to the small-x behavior of antiquark distributions which suggests that small-x data are needed for precise determination of \Delta\Sigma. We propose three sets of distributions and also provide FORTRAN library for our distributions.

Comments: 1+5 pages, LATEX, aipproc.sty, 4 eps figures. Talk given at the 14th International Spin Physics Symposium, Osaka, Japan, October 16-21, 2000