Leading-order perturbative QCD calculation of nucleon Dirac form factors.

The Dirac form factors F/sub 1//sup p//sup ,//sup n/ of nucleons are analyzed to leading order in the strong coupling constant ..cap alpha../sub s/(Q/sup 2/) and leading twist using perturbative QCD. The effects of different choices of the nucleon distribution amplitude on the leading-twist result are explored. These results are compared with recent experimental data for the proton. We show that it is possible to fit the data for F/sub 1//sup p/ in the range 10less than or equal toQ/sup 2/less than or equal to30 (GeV/c)/sup 2/ by evaluating the strong coupling constant ..cap alpha../sub s/(Q/sup 2/) at the exact gluon kinematics for each diagram of the process within the integrals over the momentum fraction which govern the perturbative QCD prediction.