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Gauge-invariant approach to meson photoproduction including the final-state interaction

H. Haberzettl·K. Nakayama·S. Krewald
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Abstract

A fully gauge-invariant (pseudoscalar) meson photoproduction amplitude off a nucleon including the final-state interaction is derived. The approach based on a comprehensive field-theoretical formalism developed earlier by one of the authors replaces certain dynamical features of the full interaction current by phenomenological auxiliary contact currents. A procedure is outlined that allows for a systematic improvement of this approximation. The feasibility of the approach is illustrated by applying it to both the neutral and charged pion photoproductions.

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H. Haberzettl, K. Nakayama, S. Krewald. 2006-09-06. Gauge-invariant approach to meson photoproduction including the final-state interaction. https://doi.org/10.1103/physrevc.74.045202

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