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arXiv · 0712.2327

Invariant Amplitudes for Pion Electroproduction

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

The invariant amplitudes for pion electroproduction on the nucleon are evaluated by dispersion relations at constant t with MAID as input for the imaginary parts of these amplitudes. In the threshold region these amplitudes are confronted with the predictions of several low-energy theorems derived in the soft-pion limit. In general agreement with Chiral Perturbation Theory, the dispersive approach yields large corrections to these theorems because of the finite pion mass.

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B. Pasquini, D. Drechsel, L. Tiator. 2007-12-14. Invariant Amplitudes for Pion Electroproduction. https://doi.org/10.1140/epja/i2007-10510-7

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