A study of pbar-p -> eta-eta-eta for masses 1960 to 2410 MeV

TL;DR

This paper reports on experimental data for the pbar-p -> 3eta reaction across a range of energies, identifying a resonance consistent with a specific meson state and providing its mass, width, and decay ratios.

Contribution

It presents new experimental measurements of pbar-p -> 3eta reactions and identifies a resonance with specific properties, advancing understanding of meson states.

Findings

Identified a dominant f_0(1500)-eta channel.

Measured the branching ratio BR[f_0(1500) -> eta-eta]/BR[f_0(1500) -> pizero-pizero] = 0.42+-0.09.

Determined the resonance mass as 2320 ± 15 MeV and width as 230 ± 35 MeV.

Abstract

Data on pbar-p -> 3eta for beam momenta 600--1940 MeV/c are presented. The strongest channel is f_0(1500)-eta from the initial pbar-p state 1S0. Together with eta-pizero-pizero data, the 3eta data determine the branching ratio BR[f_0(1500) -> eta-eta]/BR[f_0(1500) -> pizero-pizero] = 0.42+-0.09. They are consistent with a dominant contribution from an I=0, C=+1 J^{PC} = 0^{-+} resonance observed earlier in the eta-pizero-pizero data; from the combined eta-pizero-pizero and 3eta data, its mass is M = 2320 \pm 15 MeV and its width Gamma = 230+-35 MeV.