The role of the $f_0(1710)$ and $a_0(1710)$ resonances in the $D^0 \to \rho^0 \phi$, $\omega \phi$ decays

TL;DR

This paper explains the differing decay rates of $D^0$ mesons into $ ho^0 \, \phi$ and $\omega \, \phi$ by highlighting the role of the recently discovered $a_0(1710)$ and $f_0(1710)$ resonances in final state interactions.

Contribution

It introduces a mechanism involving the $a_0(1710)$ and $f_0(1710)$ resonances to explain decay rate differences in $D^0$ meson decays, linking them to specific resonance couplings.

Findings

The decay rate for $D^0 \to \rho^0 \phi$ is twice that of $D^0 \to \omega \phi$.

The $a_0(1710)$ resonance significantly enhances the $\rho^0 \phi$ decay channel.

Final state interactions via these resonances account for the observed decay ratio.

Abstract

We study the $D^0 \to \rho^0 \phi$, $\omega \phi$ decays which proceed in a direct mode via internal emission with equal rates. Yet, the experimental branching ratio for the $\rho^0 \phi$ mode is twice as big as that for the $\omega \phi$ mode. We find a natural explanation based on the extra indirect mechanism where $K^{*+} K^{*-}$ is produced via external emission and that channel undergoes final state interaction with other vector--vector channels to lead to the $\rho^0 \phi$, $\omega \phi$ final states, with transition amplitudes dominated by the $a_0(1710)$ resonance, recently discovered, and $f_0(1710)$ respectively. The large coupling of the $a_0(1710)$ to the $\rho^0 \phi$ channel is mostly responsible for this large ratio of the production rates.