Brief report on `Radiative $\phi$ decays with derivative interactions'

TL;DR

This paper investigates radiative phi decays focusing on direct scalar meson couplings and derivative interactions, showing that these can explain experimental data without kaon-loop contributions.

Contribution

It introduces a model emphasizing direct couplings with derivative interactions, challenging the traditional dominance of kaon-loop mechanisms in phi decays.

Findings

Successful fits to data using direct couplings alone

Derivative interactions significantly influence decay line shapes

Kaon-loop contributions are not essential for explaining observations

Abstract

We study the line shapes of radiative $\phi$-decays with a direct coupling of the $\phi$ meson to the $f_{0}(980)$ and $a_{0}(980)$ scalar mesons. The latter couple via derivative interactions to $\pi_0 \pi_0$ and $\pi_0 \eta$, respectively. Although the kaon-loop mechanism is usually regarded as the dominant mechanism in radiative $\phi$ decays, here we test a different possibility: we set the kaon-loop to zero and we fit the theoretical curves to the data by retaining only the direct coupling. Remarkably, satisfactory fits can be achieved, mainly due to the effects of derivative interactions of scalar with pseudoscalar mesons.