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arXiv · 1505.05619

Mass spectra of Zc and Zb exotic states as hadron molecules

Wei Chen·T. G. Steele·Hua-Xing Chen·Shi-Lin Zhu
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Abstract

We construct charmonium-like and bottomonium-like molecular interpolating currents with quantum numbers J(PC)=1(+-) in a systematic way, including both color singlet-singlet and color octet-octet structures. Using these interpolating currents, we calculate two-point correlation functions and perform QCD sum rule analyses to obtain mass spectra of the charmonium-like and bottomonium-like molecular states. Masses of the charmonium-like q_bar c c_bar q molecular states for these various currents are extracted in the range 3.85-4.22 GeV, which are in good agreement with observed masses of the Zc resonances. Our numerical results suggest a possible landscape of hadronic molecule interpretations of the newly-observed Zc states. Mass spectra of the bottomonium-like q_bar b b_bar q molecular states are similarly obtained in the range 9.92-10.48 GeV, which support the interpretation of the Zb(10610) meson as a molecular state within theoretical uncertainties. Possible decay channels of these molecular states are also discussed.

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Wei Chen, T. G. Steele, Hua-Xing Chen, Shi-Lin Zhu. 2015-08-27. Mass spectra of Zc and Zb exotic states as hadron molecules. https://doi.org/10.1103/physrevd.92.054002

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