Covalent hadronic molecules via QCD sum rules


  • Rui-Rui Dong Southeast University
  • Hua-Xing Chen Southeast University
  • Niu Su Southeast University
  • Hong-Zhou Xi Southeast University
  • Yi-Xin Yan Southeast University



hadronic molecule, covalent bond, QCD sum rules


After carefully examining Feynman diagrams corresponding to the $\bar D \Sigma_c$ hadronic molecular state, we propose a possible binding mechanism induced by shared light quarks. We systematically study its corresponding light-quark-exchange interaction using the method of QCD sum rules, and the obtained results suggest that there can be the $\bar D \Sigma_c$ covalent molecule of $I=1/2$. Our QCD sum rule analyses further indicate a model-independent hypothesis: the light-quark-exchange interaction is attractive when the shared light quarks are totally antisymmetric so that obey the Pauli principle.


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How to Cite

Dong R-R, Chen H-X, Su N, Xi H-Z, Yan Y-X. Covalent hadronic molecules via QCD sum rules. Supl. Rev. Mex. Fis. [Internet]. 2022 Aug. 1 [cited 2024 May 28];3(3):0308036 1-4. Available from: