Measurement of the top quark mass in the all-jets final state at $\sqrt{s}=$ 13 TeV and combination with the lepton+jets channel

Abstract

A top quark mass measurement is performed using 35.9 fb${}^{-1}$ of LHC proton-proton collision data collected with the CMS detector at $\sqrt{s}=$ 13 TeV. The measurement uses the $\mathrm{t}\overline{\mathrm{t}}$ all-jets final state. A kinematic fit is performed to reconstruct the decay of the $\mathrm{t}\overline{\mathrm{t}}$ system and suppress the multijet background. Using the ideogram method, the top quark mass ($m_{\mathrm{t}}$) is determined, simultaneously constraining an additional jet energy scale factor (JSF). The resulting value of $m_{\mathrm{t}}$ = 172.34 $\pm$ 0.20 (stat+JSF) $\pm$ 0.70 (syst) GeV is in good agreement with previous measurements. In addition, a combined measurement that uses the $\mathrm{t}\overline{\mathrm{t}}$ lepton+jets and all-jets final states is presented, using the same mass extraction method, and provides an $m_{\mathrm{t}}$ measurement of 172.26 $\pm$ 0.07 (stat+JSF) $\pm$ 0.61 (syst) GeV. This is the first combined $m_{\mathrm{t}}$ extraction from the lepton+jets and all-jets channels through a single likelihood function.

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/TOP-17-008 (CMS Public Pages)