A novel configuration of gluonic tetraquark state

Abstract

Inspired by the experimental measurement of the charmed hadronic state X(6900), we calculate the mass spectra of tetraquark hybrid states with configuration of \([8_{c}]_{Q\bar{Q}} \otimes [8_{c}]_{G} \otimes [8_{c}]_{Q\bar{Q}}\) in color, by virtue of QCD sum rules. The two feasible types of currents with quantum numbers \(J^{PC} = 0^{++}\) and \(0^{-+}\) are investigated, in which the contributions from operators up to dimension six are taken into account in operator product expansion (OPE). In the end, we find that, in charm sector, the tetracharm hybrid states with quantum number \(0^{++}\) has a mass of about \(6.98^{+0.16}_{-0.14} \, \text {GeV}\), while \(0^{-+}\) state mass is about \(7.26^{+0.16}_{-0.15} \, \text {GeV}\). The results overlap with the experimental observations, suggesting potential tetracharm hybrid interpretations. In bottom sector, calculation shows that the masses of tetrabottom hybrid states with quantum numbers \(0^{++}\) and \(0^{-+}\) are \(19.30^{+0.16}_{-0.17} \, \text {GeV}\) and \(19.50^{+0.17}_{-0.17} \, \text {GeV}\), respectively, which are left for future experimental confirmation.