Bounding the top quark width using final states with two charged leptons and two jets at $\sqrt{s}=13~\mathrm{TeV}$

A direct bound on the top quark decay width is presented, obtained by analysing $12.9~\mathrm{fb}^{-1}$ of proton-proton collision data collected at $\sqrt{s}=13~\mathrm{TeV}$ by the CMS experiment at the LHC. The measurement is performed by partially reconstructing the kinematics of top quark candidates from final states containing at least two charged leptons (electrons or muons) and at least two jets, where at least one jet is identified as stemming from the fragmentation and hadronization of a b quark. The observable is compared to the simulated expectations for different top quark width scenarios using a likelihood technique. Under the hypothesis of a standard model-like top quark the measurement yields limits at the $95\%$ CL of $0.6 \leq \Gamma_{\rm t} \leq 2.5~\mathrm{GeV}$, with an expected limit at $0.6 \leq \Gamma_{\rm t} \leq 2.4~\mathrm{GeV}$ for a top quark mass of $172.5~\mathrm{GeV}$.