Observation of the decay $\overline{B_s^0} \rightarrow Ï_{c2} K^+ K^- $ in the $Ï$ mass region
arXiv:1806.10576 · doi:10.1007/JHEP08(2018)191
Abstract
The $\overline{B_s^0} \rightarrow Ï_{c2} K^+ K^- $ decay mode is observed and its branching fraction relative to the corresponding $Ï_{c1}$ decay mode, in a $\pm 15 \textrm{MeV}/c^2$ window around the $Ï$ mass, is found to be $\frac{\mathcal{B}(\overline{B_s^0} \rightarrow Ï_{c2} K^+ K^-) }{ \mathcal{B}(\overline{B_s^0} \rightarrow Ï_{c1} K^+ K^-)} = (17.1 \pm 3.1 \pm 0.4 \pm 0.9)\%,$ where the first uncertainty is statistical, the second systematic and the third due to the knowledge of the branching fractions of radiative $Ï_c$ decays. The decay mode $\overline{B_s^0} \rightarrow Ï_{c1} K^+ K^- $ allows the $ B_s^0$ mass to be measured as $m(B_s^0) = 5366.83 \pm 0.25 \pm 0.27 \, \textrm{MeV}/c^2,$ where the first uncertainty is statistical and the second systematic. A combination of this result with other LHCb determinations of the $B_s^0$ mass is made.
All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2018-018.html