Searches for $B^0\to K^{+}\ddot{I}{€}^{-}\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ and $B_s^0\to K^{+}{K}^{-}\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ decays

Abstract

The first searches for $B^0\to K^{+}\ddot{I}{€}^{-}\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ and $B_s^0\to K^{+}{K}^{-}\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ decays at the LHCb experiment are conducted with $pp$ collision data corresponding to an integrated luminosity of $5.4{\text{ fb}}^{-1}$. The tau leptons are reconstructed using the $\ddot{I}{„}^{+}\to \hat{I}{¼}^{+}\overline{\hat{I}}{½}_{\ddot{I}}„\hat{I}{½}_{\hat{I}}¼$ decay and the results are presented in bins of $K^{+}\ddot{I}{€}^{-}$ or $K^{+}{K}^{-}$ mass. No signal is observed and upper limits are set on the branching fractions. The searches result in the first upper limits for $B^0\to K^{+}\ddot{I}{€}^{-}\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ decays outside the $K^{\ast }(892{)}^0$ region in $K^{+}\ddot{I}{€}^{-}$ mass and the first limits for $B_s^0\to K^{+}{K}^{-}\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ decays. The searches are recast into limits on the decays $B^0\to K^{\ast }(892{)}^0\ddot{I}{„}^{+}\ddot{I}{„}^{-}$ and $B_s^0\to \ddot{I}•(1020)\ddot{I}{„}^{+}\ddot{I}{„}^{-}$, yielding $2.8\times 10^{-4}$ ($2.5\times 10^{-4}$) and $4.7\times 10^{-4}$ ($4.1\times 10^{-4}$) at the $95\%$ ($90\%$) confidence level, respectively. For the decay $B^0\to K^{\ast }(892{)}^0\ddot{I}{„}^{+}\ddot{I}{„}^{-}$, this result improves on the current best upper limit by an order of magnitude.

All figures and tables, along with any supplementary material and additional information, are available at https://lbfence.cern.ch/alcm/public/analysis/full-details/4479 (LHCb public pages)