Comparison of the fits to data on polarized structure functions and spin asymmetries

In order to obtain polarized parton densities we make a next to leading order QCD fit using experimental data on the deep inelastic structure function g1 measured on different nucleon targets. This fit is compared with the updated fit to the corresponding spin asymmetries. We get very similar results for all fits and also for different data samples. The integrated gluon contribution at Q2=1 GeV2 is, as in our previous fits, very small. It seems that only polarized parton densities for the nonstrange quarks Δu and Δd are relatively well determined from the present polarized deep inelastic experiments