A VMD Based, Nonet and SU(3) Symmetry Broken Model For Radiative Decays of Light Mesons

TL;DR

This paper develops a Vector Meson Dominance (VMD) based model incorporating SU(3) and nonet symmetry breaking to accurately describe radiative decays of light mesons, revealing the role of glue coupling and symmetry breaking mechanisms.

Contribution

It introduces a comprehensive VMD model with SU(3) and nonet symmetry breaking, explaining radiative decays and linking to the Wess-Zumino-Witten Lagrangian.

Findings

SU(3) breaking and nonet symmetry breaking explain most data

Glue coupling effects are indistinguishable from nonet symmetry breaking

Charged K* radiative width influences model consistency

Abstract

We present a VMD based model aiming to describe all radiative decays of light mesons. We show that the SU(3) breaking mechanism proposed by Bando, Kugo and Yamawaki (BKY), supplemented by nonet symmetry breaking in the pseudoscalar sector are sufficient to provide a nice description of all data, except the charged K* radiative width. It is also shown that nonet symmetry breaking has effects which cannot be disantangled from those produced by coupling of glue to the eta' meson. Coupling of glue to $\eta$ is not found to be required by the data. Asssuming the charged K* radiative width is indeed at its presently accepted value necessitates to supplement the BKY breaking in a way which finally preserves an equivalence statement between the VMD approach to radiative decays and the Wess-Zumino-Witten Lagrangian.