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

Chapter 6: Event Selection 203
Parameter Parameter uncertainty (%) Acceptance uncertainty (%)
Trigger efficiency 2.0 (barrel), 1.9 (endcap) 0.7
Reconstruction efficiency 2.5 5.0
Muon momentum scale 1.0 0.45
Muon momentum resolution 5.0 (barrel), 9.0 (endcap) 0.48
Isolation cut efficiency 1.0 2.0
Total experimental uncertainty 5.5
Parameter δAZ(%)
Theoretical uncertainty 3.0
Total uncertainty 6.2
Table 6.16: Systematic uncertainty on Z → µµ acceptance from various sources.
The precision in the measurement of each component is reported as the ‘parameter’
uncertainty.
6.2.9 Summary of acceptance and efficiency
We summarize the Z → µµ signal acceptance in Table 6.17. The total acceptance
and the factorized values AZ and CZ are reported. The value of CZ has been corrected
by the scale factors for trigger and reconstruction efficiencies to take into account
differences between data and Monte Carlo. The scale factors are also summarized in
the table.
AZ
Z
0.486 ± 0.019
CZ
0.773 ± 0.043
Overall acceptance 0.376 ± 0.026
Trigger efficiency SF 0.981 ± 0.003 (stat) ± 0.006 (syst)
Reconstruction efficiency SF 1.000 ± 0.012 (stat) ± 0.048 (syst)
Table 6.17: Total and factorized acceptances for Z events. Trigger and reconstruction
efficiency scale factors used to correct the Monte Carlo-derived acceptance to take into
account differences between data and simulation are also shown.