Qcd Sum Rules and Compton Scattering
نویسنده
چکیده
We extend QCD sum rule analysis to moderate energy fixed angle Compton scattering. In this kinematic region there is a strong similarity to the sum rule treatment of electromagnetic form factors, although the four-point amplitude requires a modification of the Borel transform. To illustrate our method, we derive the sum rules for helicity amplitudes in pion Compton scattering and estimate their large-t behavior in the local duality approximation. (∗) A. Della Riccia fellow (∗∗) On leave from the Laboratory of Theoretical Physics, JINR, Dubna, Russian Federation
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تاریخ انتشار 1993