A measurement of the top quark pole mass $m_\mathrm{ t}^\text{ pole}$ in events where a top quark-antiquark pair ($\mathrm{ t\bar{ t}}$) is produced in association with at least one additional jet ($\mathrm{ t\bar{ t}}$+jet) is presented. This analysis is performed using proton-proton collision data at $\sqrt{ s}$ = 13 TeV collected by the CMS experiment at the CERN LHC, corresponding to a total integrated luminosity of 36.3 fb$^{ -1}$. Events with two opposite-sign leptons in the final state (e$^+$e$^-$, $\mu^+\mu^-$, e$^\pm\mu^\mp$) are analyzed. The reconstruction of the main observable and the event classification are optimized using multivariate analysis techniques based on machine learning. The production cross section is measured as a function of the inverse of the invariant mass of the $\mathrm{ t\bar{ t}}$+jet system at the parton level using a maximum likelihood unfolding. Given a reference parton distribution function (PDF), the top quark pole mass is extracted using the theoretical predictions at next-to-leading order. For the ABMP16NLO PDF, this results in $m_\mathrm{ t}^\text{ pole}$ = 172.93 $\pm$ 1.36 GeV.
Categories: hep-ex
