A Global Treatment Of VMD Physics Up To The $\phi$: I. $e^+e^-$ Annihilations, Anomalies And Vector Meson Partial Widths

TL;DR

This paper extends the Hidden Local Symmetry (HLS) model to include the full anomalous sector, successfully fitting multiple e+e- annihilation data and predicting vector meson decay widths and ratios with high accuracy.

Contribution

It introduces a comprehensive extension of the HLS model to the anomalous sector, enabling simultaneous fits to diverse experimental data and accurate predictions of vector meson decay properties.

Findings

Successful fit to multiple e+e- annihilation cross sections.

Accurate predictions of vector meson decay widths and ratios.

Consistent description of η/η' decays and spectra.

Abstract

The HLS Model, equipped with a mechanism providing the breaking of U(3)/SU(3) symmetry and an isospin symmetry breaking leading naturally to vector meson mixing, has been recently shown to successfully account for $e^+ e^- \ra \pi^+\pi^-$ cross section and for the dipion spectrum in $\tau$ decay. The present study shows that the full anomalous sector of the HLS model can be considered and is validated by the experimental data. Indeed, this extended model provides a successful simultaneous fit to the $e^+ e^- \ra \pi^+\pi^-$ data together with the available data on $e^+ e^- \ra \pi^0\gamma$, $e^+ e^- \ra \eta\gamma$ and $e^+ e^- \ra \pi^0 \pi^+\pi^-$ cross sections. It is shown that the fit of these data sets also predicts an accurate description of the $\eta/\eta^\prime \ra \pi^+ \pi^- \gamma$ decays fully consistent with the reported information on their branching fractions and spectra. Finally, one also derives from our global fits products of widths of the form $\Gamma (V \ra f_1)\Gamma(V \ra e^+ e^-) $ and ratios of the form $\Gamma (V \ra f_1)/\Gamma (V \ra f_2)$ describing decays of vector mesons to several non--leptonic final states.