Abstract

GARCIA GUDINO, D.  and  TOLEDO SANCHEZ, G.. About the inclusion of an infinite number of resonances in anomalous decays. Rev. mex. fis. [online]. 2014, vol.60, n.2, pp.123-128. ISSN 0035-001X.

The usual procedure to extract the g^eƒƒ_ωpπ effective coupling from experimental data resumes not only the ρ meson effect but also all its additional radial excitation modes. In this work, we consider a particular form of the spectrum and relations among the couplings to explicitly add the radial excitations of the ρ meson from the ω → π⁰γ and ω → 3π decays. This allows to identify the single g_ωρπ = 8.3 ± 0.8 GeV^-1, which is about 40% smaller than the effective g^eƒƒ_ωpπ. We verify the consistency with the chiral approach in the π⁰ → γγ and γ* → 3π processes, exhibiting the role of each contribution. In particular, we show that for the γ* → 3π decay, the usual relation A^VMD_γ3π= (3/2)A^WZW_γ3π, encodes all the vector contributions and not only the ρ meson one. In addition, we find that there is a strong (accidental) cancelation between the radial excitations and the contact term contributions.

Keywords : Strong decays; vector mesons; effective couplings.

        · text in English     · English ( pdf )