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arXiv · hep-ph/9904442

Generalized polarizabilities of the pion in chiral perturbation theory

C. Unkmeir·S. Scherer·A. I. L'vov·D. Drechsel
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Abstract

We present a calculation of the virtual Compton scattering amplitude for $γ^\ast+π\to γ+π$ in the framework of chiral perturbation theory at ${\cal O}(p^4)$. We explicitly derive expressions for generalized electromagnetic polarizabilities and discuss alternative definitions of these quantities.

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C. Unkmeir, S. Scherer, A. I. L'vov, D. Drechsel. 1999-04-23. Generalized polarizabilities of the pion in chiral perturbation theory. https://doi.org/10.1103/physrevd.61.034002

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