Radiative and meson decays of $Y(4230)$ in flavor SU(3)

TL;DR

This paper investigates the radiative and meson decay channels of the exotic state $Y(4230)$ using a tetraquark model, comparing theoretical predictions with experimental data to clarify its nature.

Contribution

It introduces a method for analyzing decay channels of $Y(4230)$ within the tetraquark scheme, applicable to similar charmonium-like states and decay processes.

Findings

Decay rates depend on the fifth power of pion momentum, suppressing certain channels.

Agreement with BES III data improves when considering the tail of $Y(4320)$.

Results suggest further experimental investigation in the $Y(4230)$ mass region.

Abstract

The charmonium-like exotic states $Y(4230)$ and the less known $Y(4320)$, produced in $e^+e^-$ collisions, are sources of positive parity exotic hadrons in association with photons or pseudoscalar mesons. We analyze the radiative and pion decay channels in the compact tetraquark scheme, with a method that proves to work equally well in the most studied $D^*\to \gamma/\pi+D$ decays. The decay of the vector $Y$ into a pion and a $Z_c$ state requires a flip of charge conjugation and isospin that is described appropriately in the formalism used. Rates however are found to depend on the fifth power of pion momentum which would make the final states $\pi Z_c(4020)$ strongly suppressed with respect to $\pi Z_c(3900)$. The agreement with BES III data would be improved considering the $\pi Z_c(4020)$ events to be fed by the tail of the $Y(4320)$ resonance under the $Y(4230)$. These results should renovate the interest in further clarifying the emerging experimental picture in this mass region.