$Z_c^+(3900)$ decay width in QCD sum rules

TL;DR

This paper uses QCD sum rules to analyze the decay width of the $Z_c^+(3900)$, supporting its interpretation as a tetraquark state by matching theoretical decay widths with experimental data.

Contribution

It provides a QCD sum rule calculation of the $Z_c^+(3900)$ decay widths, offering theoretical support for its tetraquark nature.

Findings

Calculated decay widths agree with experimental data

Supported the tetraquark interpretation of $Z_c^+(3900)$

Identified coupling constants for relevant decay channels

Abstract

We identify the recently observed charmonium-like structure $Z_c^\pm(3900)$ as the charged partner of the X(3872) state. Using standard techniques of QCD sum rules, we evaluate the three-point function and extract the coupling constants of the $Z_c \, J/\psi \, \pi^+$ and $Z_c \, \eta_c \, \rho^+$ vertices and the corresponding decay widths in these channels. The good agreement with the experimental data gives support to the tetraquark picture of this state.