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arXiv · 1011.5771

The vector form factor at the next-to-leading order in 1/N(C): chiral couplings L9(mu) and C88(mu) - C90(mu)

Antonio Pich·Ignasi Rosell·Juan Jose Sanz-Cillero
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Abstract

Using the Resonance Chiral Theory Lagrangian, we perform a calculation of the vector form factor of the pion at the next-to-leading order (NLO) in the 1/N(C) expansion. Imposing the correct QCD short-distance constraints, one fixes the amplitude in terms of the pion decay constant F and resonance masses. Its low momentum expansion determines then the corresponding O(p4) and O(p6) low-energy chiral couplings at NLO, keeping control of their renormalization scale dependence. At mu0=0.77 GeV, we obtain L9(mu0) = (7.9 \pm 0.4) 10^{-3} and C88(mu0)-C90(mu0)=(-4.6 \pm 0.4) 10^{-5}.

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Antonio Pich, Ignasi Rosell, Juan Jose Sanz-Cillero. 2011-03-15. The vector form factor at the next-to-leading order in 1/N(C): chiral couplings L9(mu) and C88(mu) - C90(mu). https://doi.org/10.1007/jhep02(2011)109

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