Dynamical study of $T_{ss}$ systems at a chiral quark model

• Main Authors: Ji, Jiazheng, Xing, Yuheng, Wu, Xinxing, Xu, Ning, Tan, Yue
• Format: Journal Article
• Language: English
• Published: 13-09-2024
• Subjects: Physics - High Energy Physics - Phenomenology
• DOI: 10.48550/arxiv.2409.08933

Since the discovery of $T_{cc}$ by LHCb, there has been considerable interest
in $T_{cc}$ and its heavy-flavor partners. However, the study of its strange
partner $T_{ss}$ has been largely overlooked. Within the framework of the
chiral quark model, we conducted a systematic study of the bound states of
$T_{ss}$ utilizing the Gaussian Expansion Method. Considering all physical
channels with $01^{+}$, including molecular and diquark structures. Our
calculations revealed that upon considering the coupling between diquarks and
molecular states, we identified a deep bound state with a bounding energy of 60
MeV, primarily composed of $K K^{*}$. Using the $^3P_0$ model, we calculated
the decay width of $K^{*}$ within the $KK^{*}$ bound state, which is
approximated as the decay width of the bound state in the $T_{ss}$ system. The
results indicate that due to the effect of binding energy, the decay width of
$K^{*}$ in $KK^{*}$ is approximately $3$ MeV smaller than that of $K^{*}$ in
vacuum. Additionally, resonance state calculations were performed. Utilizing
the real-scaling method, we searched for possible resonance states in the
$T_{ss}$ sysytem. Due to the strong attraction in the $[K^{*}]_8[K^{*}]_8$
configuration, four resonance states were found in the vicinity of $2.2$-$2.8$
GeV, predominantly featuring hidden-color structures, and their decay widths
are all less than $10$ MeV. We strongly recommend experimental efforts to
search for the resonance states in the $T_{ss}$ system predicted by our
calculations.