Study of the a_0(980) meson via the radiative decay phi->eta pi^0 gamma with the KLOE detector

TL;DR

This study investigates the properties of the a_0(980) meson through the radiative decay phi->eta pi^0 gamma using the KLOE detector, measuring branching ratios and extracting meson parameters.

Contribution

It provides new measurements of branching ratios and extracts the a_0(980) meson mass and couplings using experimental data and phenomenological models.

Findings

Measured branching ratios for phi->eta pi^0 gamma decay.

Extracted the a_0(980) meson mass.

Determined the meson’s couplings to eta pi^0, K^+ K^-, and phi.

Abstract

We have studied the phi->a_0(980) gamma process with the KLOE detector at the Frascati phi-factory DAPhNE by detecting the phi->eta pi^0 gamma decays in the final states with eta->gamma gamma and eta->pi^+ pi^- pi^0. We have measured the branching ratios for both final states: Br(phi->eta pi^0 gamma)=(7.01 +/- 0.10 +/- 0.20)x10^-5 and (7.12 +/- 0.13 +/- 0.22)x10^-5 respectively. We have also extracted the a_0(980) mass and its couplings to eta pi^0, K^+ K^-, and to the phi meson from the fit of the eta pi^0 invariant mass distributions using different phenomenological models.