CMS-PAS-TOP-15-014

CMS-PAS-TOP-15-014
Measurement of the top quark mass in $\mathrm{t}\bar{\mathrm{t}}$ events with a $\mathrm{J}/\psi$ from pp collisions at 8 TeV
CMS Collaboration
March 2016

Abstract: The first measurement of the top quark mass using top quark decays in the exclusive decay channel $\mathrm{t}\to(\mathrm{W}\to\ell\nu)$ , $(\mathrm{b}\to\mathrm{J}/\psi+\mathrm{X}\to\mu^+\mu^-+\mathrm{X})$ is presented. Top quark pair events in proton-proton collisions recorded with the CMS detector at a center-of-mass energy of 8 TeV are selected. The dataset corresponds to an integrated luminosity of 19.7 fb $^{-1}$ and yields 666 $\mathrm{t}\bar{\mathrm{t}}$ events containing one $\mathrm{J}/\psi$ candidate in which the $\mathrm{J}/\psi$ decays into an opposite sign muon pair. The mass of the ( $\mathrm{J}/\psi+\ell$ ) system, where $\ell$ is an electron or a muon from the W boson decay, is used to extract a top quark mass of $M_\mathrm{t} =$ 173.5 $\pm$ 3.0 (stat) $\pm$ 0.9 (syst) GeV.
Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ; These preliminary results are superseded in this paper, JHEP 12 (2016) 123. The superseded preliminary plots can be found here.

CMS Publications