0+ fully-charmed tetraquark states

Motivated by the LHCb's new observation of structures in the J/psi-pair invariant mass spectrum, which could be classified as possible cc (c) over bar(c) over bar tetraquark candidates, we systematically study 0(+) fully-charmed tetraquark states through QCD sum rules. Developing the calculation techniques to fourfold heavy hadronic systems, four different configuration currents with 0(+) are considered, and vacuum condensates up to dimension six are included in the operator product expansion. Finally, the mass values acquired for 0(+) cc (c) over bar(c) over bar tetraquark states agree well with the experimental data of the broad structure, which support that it could be a 0(+) fully-charmed tetraquark state.

Automated summary

The study examines 0(+) fully-charmed tetraquark states through QCD sum rules, with mass values matching experimental data and supporting the possibility of it being a fully-charmed tetraquark state.