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arXiv · hep-ph/9612328

Resonance Contributions to the Electromagnetic Low Energy Constants of Chiral Perturbation Theory

Robert Baur·Res Urech
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Abstract

The effective chiral Lagrangian of the strong and electromagnetic interactions of the pseudoscalar mesons at low energies depends on a set of low energy constants. We determine the contributions to the electromagnetic coupling constants at order $O(e^2 p^2)$, which arise from resonances within a photon loop. We give some implications of our results, in particular we discuss in detail the effects on the corrections to Dashen's theorem.

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Robert Baur, Res Urech. 1997-06-16. Resonance Contributions to the Electromagnetic Low Energy Constants of Chiral Perturbation Theory. https://doi.org/10.1016/s0550-3213(97)00348-9

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