Compton scattering by pion : there is no room for the off – shell effects
نویسنده
چکیده
Compton scattering by pion: there is no room for the off–shell effects. Abstract We show that the off–shell contributions in Compton scattering by pion may exist only in the single exchange diagrams. These contributions are canceled completely in the total gauge–invariant amplitude as it confirmed by one–loop calculations. It explains, in particular, some results of the chiral pertubation theory in the order p 4 but this cancelation has no relation to chiral symmetry.
منابع مشابه
Compton scattering by a pion and off-shell effects.
We consider Compton scattering by a pion in the framework of chiral perturbation theory. We investigate off–shell effects in the s– and u–channel pole diagrams. For that purpose we perform a field transformation which, in comparison with the standard Gasser and Leutwyler Lagrangian, generates additional terms at order p4 proportional to the lowest–order equation of motion. As a result of the eq...
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