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

Chapter 8: Properties of Z bosons and measurement of Z → µµ cross-section 230
[GeV]
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ATLAS Preliminary
Data 2010( s = 7 TeV)
Z → µ µ
Backgrounds
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ATLAS Preliminary
∫
Data 2010( s = 7 TeV)
Z → µ µ
Backgrounds
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L dt = 331 nb
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mµ
µ [GeV]
Figure 8.7: Muon pT versus dimuon invariant mass for signal Monte Carlo, background
Monte Carlo and data: after the muon pT cut (left) and after the isolation
cut (right).
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Data 2010( s = 7 TeV)
Z → µ µ
Backgrounds
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Data 2010 ( s=7
TeV)
Z → µ µ
ATLAS
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µ [GeV]
Figure 8.8: Track isolation ratio versus muon pT (left) and the dimuon invariant
mass spectrum (right) after the Z selection cuts. The track isolation ratio is defined
as the sum of the pT of all inner detector tracks in a cone of size ∆R