Strong and radiative decays of the scalars f0(980) and a0(980) in a hadronic molecule approach

TL;DR

This paper investigates the electromagnetic and strong decay behaviors of the scalar mesons f0(980) and a0(980) using a hadronic molecule model, emphasizing their extended structure and mixing effects.

Contribution

It introduces a covariant, gauge-invariant framework for analyzing these scalars as K Kbar molecules, including finite size effects and mixing, to better understand their decay properties.

Findings

Successful description of f0 and a0 decay widths

Quantitative analysis of f0-a0 mixing effects

Predictions for radiative decay rates

Abstract

We analyze the electromagnetic and strong decay properties of the light scalars a0(980) and f0(980) within a hadronic molecule interpretation. Both scalars are discussed within a covariant and gauge invariant model which also allows for finite size effects due to their spatially extended structure in the K Kbar-bound state picture. Allowing for f0-a0 mixing we also study its influence on the radiative decays f0/a0 to gamma gamma, f0/a0 to gamma omega, and f0/a0 to gamma rho as well as the phi production of the f0 and a0. Furthermore, we apply our formalism to describe the strong f0 to pi pi and a0 to pi eta decay properties.