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  • Open Access

Investigating the internal structure of X(6900) in the 2J/ψ decay channel

Duo-Duo Lu and Shao-Zhou Jiang*

  • Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, People’s Republic of China

  • *Contact author: jsz@gxu.edu.cn
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Phys. Rev. D 113, 094034 – Published 26 May, 2026

DOI: https://doi.org/10.1103/tnmr-tj6v

Abstract

Assuming X(6900) is a tetraquark state, the decay width of X(6900)→2J/ψ is calculated in a covariant quark model, with the diquark-antidiquark [cc][c¯c¯] picture. Two possible structures, vector-vector and axial-vector–axial-vector coupling, are investigated. The result indicates that the axial-vector–axial-vector coupling is consistent with the experiments. Additionally, as another application of the covariant quark model, the decay width of X(6900)→2ηc is predicted to be 66–88 keV.

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Phys. Rev. D 113, 094034– Published 26 May, 2026
  • Received 23 December 2025
  • Accepted 4 May 2026
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