# Exploratory study of X(4140) in QCD sum rules

## TL;DR

This study uses QCD sum rules with various currents to estimate the masses of potential X(4140) states, finding degenerate masses near 4140 MeV, but cannot determine its dominant structure.

## Contribution

It provides a comprehensive QCD sum rules analysis of X(4140) with multiple currents, exploring its possible molecular or diquark-antidiquark nature.

## Key findings

- All currents couple to states near 4140 MeV
- Degenerate masses suggest multiple states with similar mass
- Cannot determine the dominant structure of X(4140)

## Abstract

In this work, we chose three molecular and three diquark-antidiquark currents with the quark content $c\bar{c}s\bar{s}$ and $J^{PC}=0^{++},1^{++},2^{++}$, and estimated the masses and the meson coupling constants of the ground states coupling to these currents in the framework of QCD sum rules. In operator product expansion, we considered the terms including dimension eight, and we performed pole contribution tests carefully. According to our results, all of these currents couple to the ground states with degenerate masses which are in 10 MeV vicinity of X(4140). Therefore, with a QCD sum rules analysis, it is not possible to conclude that X(4140) has a dominant molecular or diquark-antidiquark content. However, there may be three states degenerate in mass, with positive charge conjugation and different isospins.