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arXiv · 2106.05550

Mass spectra for the $cc\bar{b}\bar{b}$/$bb\bar{c}\bar{c}$ tetraquark states

Abstract

We have studied the masse spectra for the $cc\bar{b}\bar{b}$/$bb\bar{c}\bar{c}$ tetraquark states with quantum numbers $J^{P}=0^{\pm},1^{\pm}$, and $2^{+}$. We systematically construct the interpolating currents with various spin-parity quantum numbers and calculate their two-point correlation functions in the framework of QCD moment sum rule method. Our calculations show that the masses are about $12.3-12.4$ GeV for the positive parity $cc\bar{b}\bar{b}$ tetraquark ground states with $J^{P}=0^+, 1^+, 2^+$, while $12.8-13.1$ GeV for the negative parity channels with $J^{P}=0^-, 1^-$. The mass predictions for the positive parity $cc\bar{b}\bar{b}$ ground states are lower than the $B_{c}B_{c}$ threshold, implying that these tetraquarks can only decay via weak interaction and thus are expected to be stable and narrow.

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Qi-Nan Wang, Zi-Heng Yang, Wei Chen, Hua-Xing Chen. 2021-06-10. Mass spectra for the $cc\bar{b}\bar{b}$/$bb\bar{c}\bar{c}$ tetraquark states. https://doi.org/10.1103/physrevd.104.014020

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