Fully Charmed Tetraquark States in 8₂₂8₂₂ Color Structure via QCD Sum Rules

Stimulated by the recent experimental results on the fully-charm tetraquark states, we systematically calculate the mass spectra of the fully-charm tetraquark states in 8₂₂8₂₂ color configuration via QCD sum rules. By constructing nine 8₂₂8₂₂ type currents with quantum numbers J^PC=0^-+, 0^--, 1^-+, 1^+-, 1^-- and 2^++, we perform analytic calculation up to dimension six in the Operator Product Expansion (OPE). We find the fully-charm tetraquark states with J^PC=1^+-, 2^++ lie around 6. 48 6. 62 GeV while the fully-charm tetraquark states with J^PC=0^-+, 0^--, 1^--, 1^-+ are about 6. 85 7. 02 GeV. Notably, the mass predictions for the cccc tetraquarks, specifically those with J^PC=2^++, align with the broad structure identified by LHCb. Moreover, the masses of fully-charm tetraquarks with J^PC=0^-+ and 1^-+ are anticipated to match closely with the mass of X (6900), considering the margin of error. Such findings hint at the presence of some 8₂₂8₂₂ components within the di-J/ structures observed by LHCb. The predictions for tetraquark states with J^PC=0^--, 1^+-, 1^-- may be accessible in the future BelleII, Super-B, PANDA, and LHCb experiments.