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  • Open Access

Discovering an unquenched dynamics mechanism for charmonium scattering

Qi Huang1,2,*, Rui Chen3,2,†, Jun He1,2,‡, and Xiang Liu2,4,5,6,7,§

  • 1School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
  • 2Lanzhou Center for Theoretical Physics, Key Laboratory of Theoretical Physics of Gansu Province, Lanzhou University, Lanzhou 730000, China
  • 3Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China
  • 4School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China
  • 5Key Laboratory of Quantum Theory and Applications of MoE, Lanzhou University, Lanzhou 730000, China
  • 6MoE Frontiers Science Center for Rare Isotopes, Lanzhou University, Lanzhou 730000, China
  • 7Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China

  • *Contact author: 06289@njnu.edu.cn
  • †Contact author: chenrui@hunnu.edu.cn
  • ‡Contact author: junhe@njnu.edu.cn
  • §Contact author: xiangliu@lzu.edu.cn
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Phys. Rev. D 113, 074007 – Published 6 April, 2026

DOI: https://doi.org/10.1103/lgmp-h4tb

Abstract

In this paper, we propose a new mechanism for charmonium scattering that utilizes the internal structure of charmonium. By capturing light flavor quarks and antiquarks from the vacuum, charm, and anticharm quarks form virtual charmed mesons, which mediate an effective one-boson exchange process. This approach accurately reproduces the di-J/ψ invariant mass spectrum observed by CMS and LHCb, demonstrating its validity. Our mechanism offers a comprehensive framework for understanding charmonium scattering and is applicable to the scattering problems involving all fully heavy hadrons, an area of increasing interest.

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Phys. Rev. D 113, 074007– Published 6 April, 2026
  • Received 24 July 2024
  • Accepted 12 March 2026
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