Theoretical study of scalar meson $a_0(1710)$ in the $\eta_c \to {\bar{K}}^0K^+\pi^- $ reaction

TL;DR

This paper uses a theoretical approach to study the scalar meson a_0(1710) in the decay of eta_c, predicting observable structures and branching ratios that can be tested in future experiments.

Contribution

It provides a dynamical generation model of the a_0(1710) and predicts specific invariant mass distributions and branching fractions for eta_c decays.

Findings

A dip structure around 1.8 GeV associated with a_0(1710)

Clear peaks of K_0^*(1430) in invariant mass distributions

Predicted branching fractions for specific eta_c decay modes

Abstract

We investigate the process $\eta_c \to {\bar{K}}^0K^+\pi^-$ by taking into account the $S$-wave ${K^*\bar{K}^*}$ and $\rho\omega$ interactions within the unitary coupled-channel approach, where the scalar meson $a_0(1710)$ is dynamically generated. In addition, the contributions from the intermediate resonances $K_0^*(1430)^{-}\to {\bar{K}}^0\pi^- $ and $K_0^*(1430)^{0}\to K^+\pi^-$ are also considered. We find a significant dip structure around 1.8~GeV, associated to the $a_0(1710)$, in the ${{\bar{K}}^0K^+}$ invariant mass distribution, and the clear peaks of the $K_0^*(1430)$ in the ${\bar{K}}^0\pi^-$ and $K^+\pi^-$ invariant mass distributions, consistent with the {\it BABAR} measurements. We further estimate the branching fractions $\mathcal{B}(\eta_c \to \bar{K}^{*0}K^{\ast+}\pi^-)= 5.5\times10^{-3}$ and $\mathcal{B}(\eta_c \to \omega\rho^+\pi^-)= 7.9\times10^{-3}$. Our predictions can be tested by the BESIII and BelleII experiments in the future.