CMS-PAS-TOP-19-005

CMS-PAS-TOP-19-005
Measurement of the jet mass distribution in highly boosted top quark decays in pp collisions at $\sqrt{s}=$ 13 TeV
CMS Collaboration
July 2019

Abstract: A measurement of the jet mass distribution in highly boosted hadronic top quark decays produced in $\text{t}\bar{\text{t}}$ events from pp collisions at $\sqrt{s}=$ 13 TeV is reported. The data were collected with the CMS detector at the LHC, and correspond to an integrated luminosity of 35.9 fb $^{-1}$ . The measurement is performed in the $\ell$ +jets channel where $\ell$ is an electron or muon. The products of the fully hadronic decay $\text{t} \rightarrow \text{b}\text{W}$ with $\text{W}\rightarrow\text{q}\bar{\text{q}}'$ are reconstructed with a single jet with transverse momentum $p_\text{T} >$ 400 GeV. The $\text{t}\bar{\text{t}}$ cross section as a function of the jet mass is unfolded at the particle level and is used to extract a value of the top quark mass of 172.56 $\pm$ 2.47 GeV. This is the first measurement of the top quark mass in the highly boosted regime with a total uncertainty comparable to those from measurements performed at threshold $\text{t}\bar{\text{t}}$ production.
Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ; These preliminary results are superseded in this paper, PRL 124 (2020) 202001. The superseded preliminary plots can be found here.

CMS Publications