Study of charmonium and charmonium-like contributions in $B^{+}\to J/\ddot{I}ˆ\hat{I}\cdot K^{+}$ decays

Abstract

A study of $B^{+}\to J/\ddot{I}ˆ\hat{I}\cdot K^{+}$ decays, followed by $J/\ddot{I}ˆ\to \hat{I}{¼}^{+}\hat{I}{¼}^{-}$ and $\hat{I}\cdot \to {\hat{I}}^3{\hat{I}}^3$, is performed using a dataset collected with the LHCb detector in proton-proton collisions at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb${}^{-1}$. The $J/\ddot{I}ˆ\hat{I}\cdot$ mass spectrum is investigated for contributions from charmonia and charmonium-like states. Evidence is found for the $B^{+}\to \left(\ddot{I}{ˆ}_2(3823)\to J/\ddot{I}ˆ\hat{I}\cdot \right)K^{+}$ and $B^{+}\to \left(\ddot{I}ˆ(4040)\to J/\ddot{I}ˆ\hat{I}\cdot \right)K^{+}$ decays with significance of 3.4 and 4.7~standard deviations, respectively. This constitutes the~first~evidence for the $\ddot{I}{ˆ}_2(3823)\to J/\ddot{I}ˆ\hat{I}\cdot$ decay.

29 pages, 7 figures. All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2021-047.html (LHCb public pages)