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arXiv · 0712.0572

A dispersive approach to pion photo- and electroproduction

D. Drechsel·B. Pasquini·L. Tiator
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Abstract

The relativistic amplitudes of pion photo- and electroproduction are calculated by dispersion relations at constant t. Several sum rules and low-energy theorems for the threshold amplitudes are investigated within this technique. The continuation of the amplitudes to sub-threshold kinematics is shown to provide a unique framework to derive the low-energy constants of chiral perturbation theory by global properties of the excitation spectrum.

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D. Drechsel, B. Pasquini, L. Tiator. 2007-12-04. A dispersive approach to pion photo- and electroproduction. https://doi.org/10.1007/s00601-007-0184-4

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