ttbar jets Update on QCD Estimation William Edson
ttbar τ + jets: Update on QCD Estimation William Edson SUNY at Albany
Chi-squared minimization � Equation: � N(x): total number of events of type x for distribution � n(x)i: number of events in bin of type x � frac(Sig): fraction of N(Remain) expected to be Signal � binfrac(x)i: fraction of events in bin of type x expected from MC or template � σi: uncertainty in bin i
Chi-squared minimization cont. � σi determined by adding in quadrature � bin error: data signal, MC QCD template other backgrounds, MC � statistical error: data: signal region (times 2) data: background region other backgrounds, MC (times 2) signal, MC signal and other backgrounds combined, MC: background region
Highest p. T bjet reconstruction June 6 After Smearing Debug (7 -23) Reapplying bug, Package Fallback, Removing Systematics code
2 nd highest p. T bjet reconstruction June 6 After Smearing Debug (7 -23) Reapplying bug, Package Fallback, Removing Systematics code
Dijet reconstruction June 6 After Smearing Debug (7 -23) Reapplying bug, Package Fallback, Removing Systematics code
Closest Top mass reconstruction June 6 After Smearing Debug (7 -23) Reapplying bug, Package Fallback, Removing Systematics code
Back-up
Results � Run 1: � chi-squared: 31. 78 � signal fraction: 0. 7415 +/- 0. 0823 � Rescale signal MC in all regions and rerun: � chi-squared: 30. 94 � signal fraction: 0. 7400+/- 0. 0792
Results � Run 1: � chi-squared: 4. 541 � signal fraction: 0. 9891+/- 0. 1460 � Rescale signal MC in all regions and rerun: � chi-squared: 3. 905 � signal fraction: 0. 9787+/- 0. 1233
Cutflow � � � � C 0: GRL C 1: Trigger C 2: Primary vertex with ntracks > 4 C 3: Electron/muon overlap, lar. Veto C 4: Jet cleaning C 5: Lepton Veto C 6: njets >= 4 with eta < 2. 5 and |jvf| > 0. 75 C 7: MET > 60 Ge. V C 8: MT < 70 Ge. V C 9: Sum ET < 500 Ge. V C 10: >= 1 bjet C 11: Tau n ≥ 1, BDTScore > 0. 7 C 12: Trigger matched tau n ≥ 1 and p. T >= 40 Ge. V C 13: MC tau object match
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