On the resummation of large corrections to the form factor of the pion in perturbative QCD

We investigate the end-point singularities of the hard scattering amplitude of the pion's electromagnetic form factor in perturbative QCD. The Q2 evolution of the end-point behavior of the wave function of the pion is determined first. We have calculated the leading double logarithmic corrections to the hard scattering amplitude up to two-loop order. The result indicates the beginning of an exponential series, similar to the famous Sudakov form factor. Extrapolating this behavior to all orders of αsub(s), we find that the end-point singularities are strongly suppressed for large Q2. It is pointed out that this effect may improve the agreement with the experimental data in the region 5 GeV2<Q2<10 GeV2. (orig.)