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Quantum loops in the Resonance Chiral Theory: improving the vector form factor

I. Rosell
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Abstract

Quantum loops in the Resonance Chiral Theory are needed to improve the implementation of non-perturbative QCD. Furthermore, the one-loop computations can predict chiral low-energy couplings at next-to-leading order, a very appealing task. We present a first calculation of the vector form factor of the pion at subleading order in the 1/N_C expansion. From the analysis of the result at large energies we justify the requirement of considering short-distance constraints from form factors with resonances in the final state. The long-distance limit of our results allows to get a next-to-leading order estimate of \ell_6.

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I. Rosell. 2006-05-30. Quantum loops in the Resonance Chiral Theory: improving the vector form factor. https://doi.org/10.1016/j.nuclphysbps.2006.09.077

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