0 v 1 4 A pr 1 99 3 ITP - US - 93 - 2 Power Corrections to QCD Sum Rules for Compton Scattering
نویسنده
چکیده
We extend previous work on sum rules for the invariant amplitudes of pion Compton scattering by deriving a complete lowest order perturbative spectral function and its leading non perturbative power corrections-for a specific combination of the two helicities (H 1 + H 2) of this process. Using some properties of a modified version of the Borel transform, we develop a method of calculation of the gluonic corrections which can be easily extended to other similar reactions, such as proton Compton scattering. A preliminary comparison of the new sum rule with the pion form factor sum rule is made.
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تاریخ انتشار 1993