Polarized Parton Distributions for Spin Asymmetries

We have used QCD and polarized deep-inelastic scattering data to construct x-dependent polarized parton distributions. These flavor dependent distributions evolve under the NLO DGLAP equations, satisfy positivity constraints and agree well with the data. We perform all of the analysis in x-space, avoiding difficulties with moments, and use these distributions to predict spin observables. The small-x behavior is sensitive to the model for the polarized gluon distribution.