A measurement of ∆Γs

Abstract

Using a dataset corresponding to 9 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 Bs0→J/ψη′$$ {B}_s^0\to J/{\psi \eta}^{\prime } $$ and Bs0→J/ψπ+π−$$ {B}_s^0\to J/\psi {\pi}^{+}{\pi}^{-} $$ are studied. The decay-width difference between the light and heavy mass eigenstates of the Bs0$$ {B}_s^0 $$ meson is measured to be ∆Γs = 0.087 ± 0.012 ± 0.009 ps−1, where the first uncertainty is statistical and the second systematic.