One loop predictions for the pion VFF in Resonance Chiral Theory

Abstract

A calculation for the one-loop pion vector form-factor in Resonance Chiral Theory is provided in this talk. The amplitude is computed up to next-to-leading order in 1/Nc and, by means of high-energy constraints, we are able to produce a prediction for the corresponding O(p4) Chiral Perturbation Theory low energy constant L9(mu)=(7.6+- 0.6) 10^{-3} at the scale mu=770 MeV.

Comments: 6 pages. Talk given at QCD@Work 2010 -International Workshop on QCD: Theory and Experiment-, 20-23 June 2010, Martina Franca, Valle d'Itria (Italy)