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arXiv · 0908.4260

Pion polarizabilities: No conflict between dispersion theory and ChPT

B. Pasquini·D. Drechsel·S. Scherer
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Abstract

Recent attempts to determine the pion polarizability by dispersion relations yield values that disagree with the predictions of chiral perturbation theory. These dispersion relations are based on specific forms for the absorptive part of the Compton amplitudes. The analytic properties of these forms are examined, and the strong enhancement of intermediate-meson contributions is shown to be connected to non-analytic structures

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B. Pasquini, D. Drechsel, S. Scherer. 2009-08-28. Pion polarizabilities: No conflict between dispersion theory and ChPT. https://arxiv.org/abs/0908.4260

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