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Doubly charmed hexaquarks in the diquark picture

Hong-Tao An^1,*, Si-Qiang Luo^2,3,4,5,†, and Xiang Liu ^2,3,4,5,‡

¹Department of Physics, Tsinghua University, Beijing 100084, China
²School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China
³Lanzhou Center for Theoretical Physics, Key Laboratory of Theoretical Physics of Gansu Province, Key Laboratory of Quantum Theory and Applications of MoE, Gansu Provincial Research Center for Basic Disciplines of Quantum Physics, Lanzhou University, Lanzhou 730000, China
⁴MoE Frontiers Science Center for Rare Isotopes, Lanzhou University, Lanzhou 730000, China
⁵Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China

^*Contact author: anht@mail.tsinghua.edu.cn
^†Contact author: luosq15@lzu.edu.cn
^‡Contact author: xiangliu@lzu.edu.cn

Phys. Rev. D 112, 054041 – Published 24 September, 2025

DOI: https://doi.org/10.1103/l4qq-pbr9

Abstract

We investigate doubly charmed hexaquark states within the diquark picture, by employing the constituent quark model and the quark-interchange model as our theoretical frameworks. Using the Gaussian expansion method, we systematically study these states, with calculating various properties such as mass spectra, internal contributions of each Hamiltonian component, root-mean-square radii, and two-body strong decay widths. Our analysis of the mass spectra reveals no stable state in this system. Furthermore, the root-mean-square radii suggest that the doubly charmed hexaquark states exhibit a compact configuration. By examining the decay widths, we identify potentially detectable states and their primary decay channels within each subsystem. Despite the large decay phase space, we still find narrow states with total widths of less than 10 MeV. This study provides a theoretical foundation for understanding the structures and interactions of doubly charmed hexaquark states and offers valuable insights for future experimental searches.

Physics Subject Headings (PhySH)

Quark model

Article Text

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Phys. Rev. D 112, 054041– Published 24 September, 2025

Vol. 112, Iss. 5 — 1 September 2025

Received 9 April 2025
Accepted 29 August 2025

DOI: https://doi.org/10.1103/l4qq-pbr9

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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Doubly charmed hexaquarks in the diquark picture

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