# On the two-body decay processes of the predicted three-body $K^*(4307)$ resonance

## TL;DR

This paper calculates the decay processes of a theoretically predicted exotic $K^*(4307)$ resonance with hidden charm, providing decay widths that can guide experimental searches and help understand its internal structure.

## Contribution

It presents the first detailed calculation of the decay channels of the $K^*(4307)$ resonance, linking its decay widths to its exotic nature and internal structure.

## Key findings

- Decay widths for $J/\psi K^*$, $\bar{D}D_s$, $\bar{D}D_s^*$, and $\bar{D}^* D_s^*$ channels.
- Decay mechanisms involve triangular loops related to the resonance's internal structure.
- Results support the $K^*(4307)$ as an exotic meson with hidden charm, not a simple quark-antiquark state.

## Abstract

In a recent theoretical work, Phys. Lett. B785, 112 (2018), we proposed that a $K^*$ resonance with hidden charm content arises from the $KD\bar D^*$ dynamics, where the $D\bar D^*$ system is treated as a $Z_c(3900)$ or $X(3872)$. With the motivation of determining its further properties, which can be observed in experiments, we now present a calculation of the decay processes of this $K^*$, namely $K^*(4307)$, to two-body channels. Particularly, we consider the decay channels $J/\psi K^*(892)$, $\bar{D}D_s$, $\bar{D}D_s^*$ and $\bar{D}^* D_s^*$. The mechanisms of the decay to these channels involve triangular loops and are a consequence of the internal structure of the state. Thus, the values found for the decay widths of the proposed $K^*(4307)$ are related to its nature and should be valuable for carrying on an experimental study of the $K^*(4307)$. A $K^*$ state with such a mass (in the charmonium region) and quantum numbers is a clear manifestation of an exotic meson, since, having hidden charm (i.e., a $c\bar c$ pair), its mass and quantum numbers can not be explained within a quark-antiquark description.