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arXiv · hep-ph/9902326

Radiative Decays, Nonet Symmetry and SU(3) Breaking

Abstract

We re-examine the problem of simultaneously describing in a consistent way all radiative and leptonic decays of light mesons (V -> P gamma, P -> V gamma, P -> gamma gamma, V -> e^+ e^-). For this purpose, we rely on the Hidden Local Symmetry model in both its anomalous and non--anomalous sectors. We show that the SU(3) symmetry breaking scheme proposed by Bando, Kugo and Yamawaki, supplemented with nonet symmetry breaking in the pseudoscalar sector, allows one to reach a nice agreement with all data, except for the K^{*+/-} radiative decay. An extension of this breaking pattern allows one to account for this particular decay mode too. Considered together, the whole set of radiative decays provides a pseudoscalar mixing angle theta_P ~ -11^o and a value for theta_V which is ~ 3^o from that of ideal mixing. We also show that it is impossible, in a practical sense, to disentangle the effects of nonet symmetry breaking and those of glue inside the eta', using only light meson decays.

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BibTeXRIS

M. Benayoun, L. DelBuono, S. Eidelman, V. N. Ivanchenko, H. B. O'Connell. 1999-05-12. Radiative Decays, Nonet Symmetry and SU(3) Breaking. https://doi.org/10.1103/physrevd.59.114027

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