Measurement of spin correlations in top pair events in the lepton + jets channel with the matrix element method at 8TeV8 \text{TeV}

Collaboration
2015
20 pages
Report number:
  • CMS-PAS-TOP-13-015
Experiments:

Citations per year

20152016201781
Abstract:
The consistency of the top quark pair events produced with standard model (SM) correlated spins is tested in the muon+jets final state. The events are obtained from pppp collisions at a center of mass energy of s=8 TeV\sqrt{s} = 8 \text{ TeV}, corresponding to an integrated luminosity of Ldt=19.7fb1\int Ldt\, =\, 19.7\, \text{fb}^{-1}, collected with the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The data agree with the SM hypothesis within 2.2 σ\sigma (standard deviation) and agree with the uncorrelated hypothesis within 2.9 σ\sigma based on a hypothesis testing procedure. In addition, using a template fit method, the fraction of events which show SM spin correlations ff, is extracted. This fraction is measured to be f=0.72±0.09(stat)0.13+0.15(syst)f\,=\,0.72\,\pm\,0.09\,\mathrm{(stat)}\, ^{+\,0.15}_{-\,0.13}\,\mathrm{(syst)}, representing the most precise measurement of this quantity in the lepton+jets channel at present.
Note:
  • Preliminary results
  • Data
  • p p: scattering
  • p p: colliding beams
  • top: pair production
  • spin: correlation
  • CERN LHC Coll
  • CMS
  • experimental results
  • 8000 GeV-cms