Fully-strange tetraquarks: fall-apart decays and experimental candidates

TL;DR

This work extends a prior mass spectrum analysis of fully-strange tetraquarks by evaluating their fall-apart decays in a quark-exchange framework. It links predicted $T_{ss\bar{s}\bar{s}}$ states across $1S$, $2S$, and $1P$ waves to experimental signals, identifying plausible matches such as $X(2300)$ with $T_{(4s)1^{+-}}(2323)$ and $X(2500)$ with $T_{(4s)0^{-+}}(2481)$, while predicting predominantly narrow widths of order $O(10)$ MeV. The results provide concrete decay channels for experimental searches, e.g., $φφ$, $φφ(1680)$, $η^{(′)}φ$, $η^{(′)}h_1(1415)$, and $φ f_2^{′}(1525)$, and indicate areas where the states may be observed or constrained in BESIII/Belle-II data. Overall, the study clarifies which fully-strange tetraquark states are most accessible through their fall-apart decays and how current resonances fit or challenge the tetraquark interpretation, highlighting potential short-distance components in the spectrum.

Abstract

We presents a systematic analysis of the fall-apart decays for the $1S$, $1P$, and $2S$-wave fully-strange tetraquark states. It shows that most of the fully-strange tetraquark states have a relatively narrow fall-apart decay width of $\mathcal{O}(10)$ MeV. The newly observed axial-vector state $X(2300)$ at BESIII may favor the low-lying $1S$-wave $1^{+-}$ state $T_{(4s)1^{+-}}(2323)$, while the $X(2500)$ resonance observed in the earlier BESIII experiment may favor the low-lying $1P$-wave $0^{-+}$ state $T_{(4s)0^{-+}}(2481)$. Some fully-strange tetraquark states predicted in theory can be searched for in their dominant fall-apart decay channels in experiment, such as $φφ$, $φφ(1680)$, $η^{(\prime)}φ$, $η^{(\prime)}h_1(1415)$, and $φf_2^{\prime}(1525)$, to which they have relatively large couplings.

Figures (1)

• Figure 1: The fall-apart decays of a $T_{ss\bar{s}\bar{s}}$ state induced by the interactions $V_{ij}$ ($ij\neq 13,24$ or $ij\neq 14,23$) between inner quarks of final hadrons $B$ and $C$.