Testing the predicted dynamically generated hidden charm $X$ scalar state through the $D\bar D$ invariant mass spectrum and the radiative decay of the $\psi(3770)$

TL;DR

This paper models the generation of hidden charm scalar resonances from meson interactions, predicting a new state near the $D\bar D$ threshold that could explain observed spectral enhancements and be detected via radiative decays.

Contribution

It introduces a dynamical model that predicts a new hidden charm scalar resonance near the $D\bar D$ threshold, linking it to experimental observations and decay processes.

Findings

Predicted a hidden charm scalar resonance near the $D\bar D$ threshold.

Suggested this resonance explains the $D\bar D$ mass spectrum enhancement.

Estimated decay widths indicating potential observability in experiments.

Abstract

In this work we present our model that dynamically generates resonances from charmed and light pseudoscalar and vector mesons. The model generates a rich spectrum of charmed and hidden charm scalar and axial resonances, most of them which can be associated with observed states. Other states are predicted, in particular a hidden charm scalar resonance with mass close to the $D\bar D$ threshold. For this resonance we present calculations which show that an observed enhancement in the $D\bar D$ mass spectrum measured by Belle in reactions producing $D\bar D J/\psi$ in the final state could be originated by this predicted state. We also present theoretical calculations on the radiative decay width of the $\psi(3770)$ into this state. The predicted branching fractions suggest that this predicted state could be observed by BES with statistics of one year run in the $\psi(3770)$ peak.