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This update focuses on QCD estimation using chi-squared minimization method by William Edson from SUNY at Albany. The equation and results, including ensemble tests with Gaussian fit, are discussed along with the backup proceeding on acceptance and efficiency work. The results cover various reconstructions scenarios and detailed cutflow analysis.
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ttbarτ + 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
Results • Chi-square: 3.747 • signal fraction: 0.91933 +/- 0.157592 • signal fraction for all data: 0.819601
Ensemble tests with result signal fraction Results with Gaussian Fit Associated Errors Mean: 0.764889 +/- 0.002659 Sigma: 0.0805555 +/- 0.0020661
Linear Fit with Signal Fraction from 0.1 - 0.8 y(0): -0.00998677 +/- 0.05173513 slope: 0.912698 +/- 0.1009633
Proceeding Acceptance and Efficiency Work • Efficiency: Limiting to events in 105200 sample satisfying: • contain truth matched taus • single prong • muonVeto and eleBDTMedium == 0 • calo-seeded taus • Acceptance: Using all MC types • Nrec: MC events passing entire cutflow • Ngen: 105200 events using mc and trueTau branch information matched to single prong, BDTJetScore > 0.7 taus
Highest pTbjet reconstruction • Results for plot: • chi-square: 7.341 • p-value: 0.7709 • ndf: 11 • chi/ndf: 0.6674
2nd highest pTbjet reconstruction • Results for plot: • chi-square: 13.76 • p-value: 0.3166 • ndf: 12 • chi/ndf: 1.147
Dijet reconstruction • Results for plot: • chi-square: 6.133 • p-value: 0.8643 • ndf: 11 • chi/ndf: 0.5575
Closest Top mass reconstruction • Results for plot: • chi-square: 5.342 • p-value: 0.8035 • ndf: 9 • chi/ndf: 0.5936
Cutflow • C0: GRL • C1: Trigger • C2: Primary vertex with ntracks > 4 • C3: Electron/muon overlap, larVeto • C4: Jet cleaning • C5: Lepton Veto • C6: njets >= 4 with eta < 2.5 and |jvf| > 0.75 • C7: MET > 60GeV • C8: MT < 70GeV • C9: Sum ET < 500GeV • C10: >= 1 bjet • C11: Tau n ≥ 1, BDTScore > 0.7 • C12: Trigger matched tau n ≥ 1 and pT >= 40GeV • C13: MC tau object match