Measurement of the $B_s^0\to J/\ddot{I}ˆK_S^0$ branching fraction

Abstract

The $B_s^0\to J/\ddot{I}ˆK_S^0$ branching fraction is measured in a data sample corresponding to 0.41$f{b}^{-1}$ of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2${\hat{I}}^2$ measurement from $B^0\to J/\ddot{I}ˆK_S^0$ The time-integrated branching fraction is measured to be $BF(B_s^0\to J/\ddot{I}ˆK_S^0)=(1.83\pm 0.28)\times 10^{-5}$. This is the most precise measurement to date.