$Ï^-\toÏ^-η^{(\prime)}ν_Ï$ decays
arXiv:1307.8277
Abstract
The vector and scalar form factors relevant to the second-class current $Ï^-\toÏ^-η^{(\prime)}ν_Ï$ processes are evaluated supplementing Chiral Perturbation Theory with the inclusion of resonances as explicit degrees of freedom. While the vector contribution is essentially fixed from knowledge of the two-pion vector form factor, the scalar form factor demands a coupled channel dispersive analysis to obtain robust predictions for the detection of these decay modes.
4 pages, no figures. Contribution to the Proceedings of the Moriond QCD 13 Conference held in La Thuile, 9-16 March, 2013