Analysis of the Y(4140) with QCD sum rules

TL;DR

This paper investigates the mass of a hypothesized scalar molecular state using QCD sum rules, finding it inconsistent with experimental data and suggesting it is likely a virtual state rather than the observed Y(4140).

Contribution

The study applies QCD sum rules to analyze the D_s* D_s* molecular state hypothesis for Y(4140), providing mass predictions and discussing their implications.

Findings

Predicted mass of D_s* D_s* molecular state is about 4.43 GeV.

Predicted mass is inconsistent with experimental data.

D_s* D_s* is likely a virtual state, not related to Y(4140).

Abstract

In this article, we assume that there exists a scalar $D_s^\ast {\bar D}_s^\ast$ molecular state in the $J/\psi \phi$ invariant mass distribution, and study its mass using the QCD sum rules. The predictions depend heavily on the two criteria (pole dominance and convergence of the operator product expansion) of the QCD sum rules. The value of the mass is about $M_{D_s^\ast {\bar D}_s^\ast}=(4.43\pm0.16) \rm{GeV}$, which is inconsistent with the experimental data. The $D_s^\ast {\bar D}_s^\ast$ is probably a virtual state and not related to the meson Y(4140). Other possibility, such as a hybrid charmonium is not excluded.