W-like measurement of the Z boson mass using dimuon events collected in pp collisions at s=7 TeV\sqrt{s} = 7~\mathrm{TeV}

Collaboration
2016
18 pages
Report number:
  • CMS-PAS-SMP-14-007
Experiments:

Citations per year

2016201820202022202402468
Abstract:
The mass of the Z boson is measured using a sample of Zμμ\mathrm{Z}\rightarrow\mu\mu events, where one of the two muons is removed from the event to form the Wlike\mathrm{W}^\mathrm{like} candidate. This procedure provides a proof of principle and a quantitative validation of analysis techniques developed for a high-precision measurement of the W boson mass in Wμν\mathrm{W}\rightarrow\mu\nu events. The study is made on the basis of a dimuon data sample collected by CMS at s=7 TeV\sqrt{s} = 7~\mathrm{TeV}, corresponding to an integrated luminosity of 4.7 fb14.7~\mathrm{fb}^{-1}. A set of 2×1052\times10^5 Zμμ\mathrm{Z} \rightarrow \mu \mu candidates is used to extract the result. The Z mass is extracted through the Wlike\mathrm{W}^\mathrm{like} lepton pTp_\mathrm{T}, transverse mass and transverse missing energy distributions, and is compatible with the world-average value, MZPDG=91187.6±2.1 MeVM_\mathrm{Z}^\mathrm{PDG} = 91187.6 \pm 2.1~\mathrm{MeV}. The lowest uncertainty is obtained when using the Wlike+\mathrm{W}^\mathrm{like+} transverse mass, for which MZWlike=91206±36 (stat.)±30 (syst.) MeVM_\mathrm{Z}^\mathrm{W_{like}} = 91206 \pm 36~(\mathrm{stat.}) \pm 30~(\mathrm{syst.})~\mathrm{MeV}.
Note:
  • Preliminary results
  • Data
  • p p: colliding beams
  • mass: transverse
  • Z0: mass: measured
  • p p: scattering
  • Z0: leptonic decay
  • muon: pair production
  • transverse energy: missing-energy
  • lepton: transverse momentum
  • lepton: transverse energy