Study of a0(980)--f0(980) mixing

TL;DR

This study investigates the mixing between the scalar mesons a0(980) and f0(980) using large J/psi and psi' datasets, providing evidence for their transition and setting limits on their mixing parameters.

Contribution

It presents the first evidence for f0(980) to a0(980) mixing with a significance of 3.4 sigma and measures the associated branching ratios and mixing intensities.

Findings

Evidence for f0(980) to a0(980) transition at 3.4 sigma significance.

Upper limits set on the branching ratios of the mixing processes.

Quantitative measurements of the mixing intensities.

Abstract

Using samples of 2.25*10^8 J/psi events and 1.06*10^8 psi' events collected with the BES III detector, we study the f0(980) to a0(980) and a0(980) to f0(980) transitions in the processes J/psi --> phi f0(980) --> phi a0(980) and chi_c1 --> pi^0 a0(980) --> pi^0 f0(980), respectively. Evidence for f0(980) --> a0(980) is found with a significance of 3.4 sigma, while in the case of a0(980) --> f0(980) transition, the significance is 1.9 sigma. Measurements and upper limits of both branching ratios and mixing intensities are determined.