Measurement of the B s 0 → J / ψK S 0 $$ {\textrm{B}}_{\textrm{s}}^0\to \textrm{J}/{\uppsi \textrm{K}}_{\textrm{S}}^0 $$ effective lifetime from proton-proton collisions at s $$ \sqrt{s} $$ = 13 TeV

Abstract

Abstract The effective lifetime of the B s 0 $$ {\textrm{B}}_{\textrm{s}}^0 $$ meson in the decay B s 0 → J / ψK S 0 $$ {\textrm{B}}_{\textrm{s}}^0\to \textrm{J}/{\uppsi \textrm{K}}_{\textrm{S}}^0 $$ is measured using data collected during 2016–2018 with the CMS detector in s $$ \sqrt{s} $$ = 13 TeV proton-proton collisions at the LHC, corresponding to an integrated luminosity of 140 fb −1. The effective lifetime is determined by performing a two-dimensional unbinned maximum likelihood fit to the B s 0 $$ {\textrm{B}}_{\textrm{s}}^0 $$ meson invariant mass and proper decay time distributions. The resulting value of 1.59 ± 0.07(stat) ± 0.03(syst) ps is the most precise measurement to date and is in good agreement with the expected value.

Keywords

• B Physics
• Hadron-Hadron Scattering
• Lifetime