Interpretation of Y${}_b$(10753) as a tetraquark and its production mechanism

Recently, the Belle Collaboration has updated the analysis of the cross sections for the processes e${}^{+}$e${}^{\text{â}}\text{ˆ}\text{’}$ $\to$ ${\rm Y}$(nS)π${}^{+}$π${}^{-}$; nS = 1S, 2S, 3S in the e${}^{+}$e${}^{-}$ center-of-mass energy range from 10.52 to 11.02 GeV, taken at the KEKB asymmetric e${}^{+}$e${}^{-}$-collider. A new structure, called here Y${}_b$(10753), with the mass M(Y${}_b$) = (10752.7 ± 5.9${}_{-1.1}^{+0.7}$) MeV and the Breit-Wigner width Γ(Y${}_b$) = (35.5${}_{-11.3-3.3}^{+17.6+3.9}$) MeV was observed. We interpret Y${}_b$(10753) as a compact J${}^{PC}$ = 1${}^{--}$ state with a dominant tetraquark component. The mass eigenstate Y${}_b$(10753) in our approach is a linear combination of the diquark-antidiquark and b$\overline{b}$ components due to the mixing via gluonic exchanges in the 't Hooft diagrams, shown recently to arise in the large-N${}_c$ limit. The mixing angle Y${}_b$-${\rm Y}$(5S) can be estimated from Γ${}_{ee}$(Y${}_b$), for which only a 90% C.L. upper limit is known currently. The resonant part of the dipion invariant mass spectrum in Y${}_b$(10753) $\to$ ${\rm Y}$(1S)π${}^{+}$π${}^{-}$ and the corresponding angular distribution of π${}^{+}$ in the dipion rest frame are presented. The mixing provides a plausible mechanism for Y${}_b$(10753) production in high energy collisions from the b$\overline{b}$ component in its Fock space. Using this framework, we work out the Drell-Yan and prompt production cross sections for pp $\to$ Y${}_b$(10753) $\to$ ${\rm Y}$(nS)π${}^{+}$π${}^{-}$ at the LHC.