0 v 1 2 3 D ec 1 99 8 Scheme dependence of NLO corrections to exclusive processes
نویسنده
چکیده
We apply the so-called conformal subtraction scheme to predict perturba-tively exclusive processes beyond the leading order. Taking into account evolution effects, we study the scheme dependence for the photon-to-pion transition form factor and the electromagnetic pion form factor at next-to-leading order for different pion distribution amplitudes. Relying on the con-formally covariant operator product expansion and using the known higher order results for the polarized deep inelastic scattering, we are able to predict perturbative corrections to the hard-scattering amplitude of the photon-to-pion transition form factor beyond the next-to-leading order in the conformal scheme restricted to the conformal limit of the theory.
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