Eur. Phys. J. C (2025) 85: 1303
https://doi.org/10.1140/epjc/s10052-025-15021-z

Regular Article - Theoretical Physics

Hidden and double charm-strange tetraquarks and their decays in a potential quark model

¹ Institute of High Energy Physics, Chinese Academy of Sciences, 100049, Beijing, China
² University of Chinese Academy of Sciences, 100049, Beijing, China
³ Department of Physics, Hunan Normal University, and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, 410081, Changsha, China
⁴ Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Hunan Normal University, 410081, Changsha, China
⁵ Center for High Energy Physics, Henan Academy of Sciences, 450046, Zhengzhou, China

^a This email address is being protected from spambots. You need JavaScript enabled to view it.
^b This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 22 August 2025
Accepted: 1 November 2025
Published online: 14 November 2025

Abstract

We carry out a systematic study of the 1S-wave hidden and double charm-strange tetraquarks $cs\overline{c}\overline{s}$ and $cc\overline{s}\overline{s}$ in a nonrelativistic potential quark model framework with the explicitly correlated Gaussian method, and the mass spectra, color-spin configurations and possible decay modes are obtained. We find that although these states are all above their open flavor thresholds, their rearrangement decay widths are rather narrow which can be understood by the mismatching of the wave functions between the initial and final states. It implies that the tetraquarks of $cs\overline{c}\overline{s}$ and $cc\overline{s}\overline{s}$ may have a good chance to exist as genuine tetraquark states. It also shows that the color-spin configurations of the $cs\overline{c}\overline{s}$ and $cc\overline{s}\overline{s}$ systems are quite different. We find that for a physical state of $cs\overline{c}\overline{s}$ its color configurations can be dominated by either the ${|11⟩}_c$ or ${|88⟩}_c$ ones. It suggests that some hidden charm-strange tetraquark states may strongly couple to two color-singlet hadrons if the kinematics and dynamics allow. In contrast, we find that the color configurations ${|11⟩}_c$ and ${|88⟩}_c$ in a double charm-strange $cc\overline{s}\overline{s}$ state are rather compatible. It may suggest that an overall color-singlet tetraquark (i.e. a genuine color-singlet) should always play a role in the $T_{cc\overline{s}\overline{s}}$ states. We also demonstrate that our formalism contain the spin symmetry relations in the heavy quark symmetry and heavy quark spin symmetry limit which are the same as those derived in the Born–Oppenheimer model. Discussions taking into account some experimental candidates are presented, and suggestions on further experimental searches are also made.