A measurement of $\hat{I}”\hat{I}{“}_s$

Abstract

Using a dataset corresponding to $9{\mathrm{fb}}^{-1}$ of integrated luminosity collected with the LHCb detector between 2011 and 2018 in proton-proton collisions, the decay-time distributions of the decay modes $B_s^0\to J/\ddot{I}ˆ\hat{I}{\cdot }^{\prime }$ and $B_s^0\to J/\ddot{I}ˆ\ddot{I}{€}^{+}\ddot{I}{€}^{-}$ are studied. The decay-width difference between the light and heavy mass eigenstates of the $B_s^0$ meson is measured to be $\hat{I}”\hat{I}{“}_s=0.087\pm 0.012\pm 0.009{\mathrm{ps}}^{-1}$, where the first uncertainty is statistical and the second systematic.

All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-025.html