Measurement of the Z boson cross-section in - Harvard University ...

Chapter 8: Properties of Z bosons and measurement of Z → µµ cross-section 228
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Figure 8.5: SCT (left) and TRT (right) hits on inner detector tracks matched to
muon spectrometer tracks for signal Monte Carlo and data after the full Z selection.
outside the band, but very few within the band.
Figure 8.8 (left) shows the track isolation ratio versus muon pT , in which all Z
cuts have been applied except the isolation cut. Figure 8.8 (right) shows the dimuon
invariant mass distribution from data and Monte Carlo after the Z selection.
Figure 8.9 shows the dimuon invariant mass distribution for signal Monte Carlo
and data separately for events in which both muons are in the barrel, both in the
endcap, and one muon in the barrel and one in the endcap.
Figure 8.10 shows the pT and rapidity distributions of the Z bosons.
8.1.2 Fitting the Z peak and extraction of Z mass resolution
Figure 8.11 shows an unbinned fit to the dimuon invariant mass spectrum in data.
The fitting function is a theoretical lineshape which includes both Z and virtual
photon contributions to the Drell-Yan production, convolved with a Gaussian function