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arXiv · hep-ph/0311321

Hadronic processes and electromagnetic corrections

Ignazio Scimemi
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Abstract

The inclusion of electromagnetism in a low energy effective theory is worth further study in view of the present high precision experiments (muon g-2, pi_0->2 gamma, tau decays, etc.). In particular in many applications of chiral perturbation theory, one has to purify physical matrix elements from electromagnetic effects. The theoretical problems that I want to point out here are following: the splitting of a pure QCD and a pure electromagnetic part in a hadronic process is model dependent: is it possible to parametrise in a clear way this splitting? What kind of information (scale dependence, gauge dependence,..) is actually included in the parameters of the low energy effective theory? I will attempt to answer these questions introducing a possible convention to perform the splitting between strong and electromagnetic parts in some examples.

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Ignazio Scimemi. 2003-11-25. Hadronic processes and electromagnetic corrections. https://doi.org/10.1016/s0920-5632(04)00022-2

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