Signature of an $h_1$ state from $J/\psi \to \eta K^{*0}\bar{K}^{*0}$ and theoretical description of the $Z_c(3900)$ and $Z_c(4020)$ as $D \bar D^*$ and $D^* \bar D^*$ molecular states

TL;DR

This paper proposes an empirical interpretation of a new $h_1$ state in $J/$ decay data and offers a theoretical model describing $Z_c(3900)$ and $Z_c(4020)$ as molecular states of $D$ mesons.

Contribution

It introduces a new $h_1$ state explanation and models $Z_c$ states as $D ar D^*$ and $D^* ar D^*$ molecules, advancing understanding of exotic hadrons.

Findings

Identification of a new $h_1$ state near the $K^{*0}ar{K}^{*0}$ threshold.

Theoretical description of $Z_c(3900)$ and $Z_c(4020)$ as molecular states.

Enhanced understanding of exotic charmonium-like states.

Abstract

In this talk we address two topics: The first one is an empirical explanation in terms of a new state $h_1$ of the peak in the $K^{*0}\bar{K}^{*0}$ invariant mass distribution close to threshold of this channel in the $J/\psi \to \eta K^{*0}\bar{K}^{*0}$ decay. The second one is a theoretical description of the isospin $I=1$ $Z_c(3900)$ and $Z_c(4020)$ states in terms of molecular states of $D \bar D^*+ cc$ and $D^* \bar D^*$.