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

Chapter 9: Discussion and Outlook 238
Figure 9.1: The measured values of the Z cross-section in the electron and muon
channels as well as the combined value from the two channels. Note that the size
of the dataset used for the electron channel measurement is 316 nb −1 . The theory
prediction is from the FEWZ program using the MRST2008 NNLO PDF set. For the
data points, the total uncertainties are shown.
We conclude that the modeling of the Z boson production cross-section using QCD
calculations up to order α 2 S is accurate in the limit of current measurements.
9.2 Outlook
In this section, we show distributions of Z boson kinematic variables obtained
with a 3.37 pb −1 dataset, which is larger than the dataset used for the cross-section
measurement by a factor of ≈ 10.2.
Figure 9.3 shows an unbinned fit to the dimuon invariant mass spectrum in data,
using the fitting function described in Section 8.1.2. The mean and width obtained
from the fit are reported in Table 9.3, together with corresponding values from Monte