# The $ss \bar s \bar s$ tetraquark states and the newly observed structure $X(2239)$ by BESIII Collaboration

## TL;DR

This paper studies the mass spectrum of $ss ar s ar s$ tetraquarks using a relativized quark model and suggests the observed $X(2239)$ resonance is a $P$-wave $ss ar s ar s$ tetraquark, providing decay predictions for future experiments.

## Contribution

It is the first to assign the $X(2239)$ structure as a $P$-wave $ss ar s ar s$ tetraquark within a relativized quark model framework.

## Key findings

- The $X(2239)$ can be described as a $P$-wave $ss ar s ar s$ tetraquark.
- Mass spectra are consistent with the observed resonance.
- Decay behaviors offer guidance for experimental verification.

## Abstract

We investigate the mass spectrum of the $ss \bar s \bar s$ tetraquark states within the relativized quark model. By solving the Schr\"{o}dinger-like equation with the relativized potential, the masses of the $S-$ and $P-$wave $ss \bar s \bar s$ tetraquarks are obtained. The screening effects are also taken into account. It is found that the observed resonant structure $X(2239)$ in the $e^+e^- \to K^+K^-$ process by BESIII Collaboration can be assigned as a $P-$wave $1^{--}$ $ss \bar s \bar s$ tetraquark state. Furthermore, the radiative transition and strong decay behaviors of this structure are also estimated, which can provide helpful information for future experimental searches.