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ttbar  τ + jets : Update on QCD Estimation

ttbar  τ + jets : Update on QCD Estimation. William Edson SUNY at Albany. All Four Histogram Fit Selection. Results for Fit: Signal Fraction: 0.666737±0.038823 Chi2: 65.723 Meas. Used: 69 σ : 164.427±9.574 Ensemble Results: Mean: 0.608899±0.00123928 chi2: 4.49706 NDF: 8.

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ttbar  τ + jets : Update on QCD Estimation

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  1. ttbarτ + jets:Update on QCD Estimation William Edson SUNY at Albany

  2. All Four Histogram Fit Selection • Results for Fit: • Signal Fraction: 0.666737±0.038823 • Chi2: 65.723 • Meas. Used: 69 • σ: 164.427±9.574 • Ensemble Results: • Mean: 0.608899±0.00123928 • chi2: 4.49706 • NDF: 8

  3. Only MET and Dijet Mass Fit Selection Input Fraction 0.639599 • Results for Fit: • Signal Fraction: 0.639599±0.0435993 • Chi2: 28.0518 • Meas. Used: 32 • σ: 157.735±10.7522 • Ensemble Results: • Mean: 0.610350±0.00123522 • chi2: 5.81292 • NDF: 7

  4. Only MET and Highest bjet Reconstruction Fit Selection • Results for Fit: • Signal Fraction: 0.627044±0.0438223 • Chi2: 29.579 • Meas. Used: 32 • σ: 154.638±10.8072 • Ensemble Results: • Mean: 0.594567±0.00124826 • chi2: 10.4607 • NDF: 9

  5. Only MET and 2ndbjet ReconstructionFit Selection • Results for Fit: • Signal Fraction: 0.634902±0.0427204 • Chi2: 34.5105 • Meas. Used: 31 • σ: 156.576±10.5355 • Ensemble Results: • Mean: ? • chi2: ?

  6. MET, Dijet Mass and Highest bjetReconstruction Fit Selection • Results for Fit: • Signal Fraction: 0.65095±0.0415496 • Chi2: 44.576 • Meas. Used: 51 • σ: 160.534±10.2467 • Ensemble Results: • Mean: 0.609824±0.00122732 • chi2: 4.50061 • NDF: 7

  7. MET, Highest and 2nd Reconstruction Fit Selection Input Fraction 0.627044 • Results for Fit: • Signal Fraction: 0.646003±0.0407967 • Chi2: 51.0783 • Meas. Used: 50 • σ: 159.314±10.0611 • Ensemble Results: • Mean: 0.571676±0.00122598 • chi2: 6.46039 • NDF: 8

  8. Back-up

  9. Histograms Used in Fit Comparisons MET Dijet Mass

  10. Histograms Used in Fit Comparisons Highest pTbjet Reconstruction 2nd Highest pTbjet Reconstruction The other background histograms titled incorrectly due to error in the analysis code, has been corrected.

  11. New Fits for Ensemble Tests

  12. Cutflow • C0: GRL • C1: Trigger • C2: Primary vertex with ntracks > 4 • C3: Electron/muon overlap, larVeto • C4: Jet cleaning • C5: Lepton Veto • C6: tau n ≥ 1 • C7: njets >= 4 with eta < 2.5 and |jvf| > 0.75 • C8: MET > 60GeV • C9: MT < 80GeV • C10: >= 1 bjet • C11: Trigger matched tau n ≥ 1 and pT >= 40GeV • C12: MC tau object match

  13. 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

  14. Chi-squared minimization cont. • σi determined using factors for: • bin error: • data • signal, MC • QCD template • other backgrounds, MC • statistical error: • data: signal region • other backgrounds, MC • signal, MC • QCD template (uncertainty of background region data and all MC background region carried through via default SumW2

  15. Highest pTbjet reconstruction • Results for plot: • chi-square: 18.798 • p-value: 0.4044 • ndf: 18 • chi/ndf: 1.044

  16. 2nd Highest pTbjet reconstruction • Results for plot: • chi-square: 20.82 • p-value: 0.2346 • ndf: 17 • chi/ndf: 1.225

  17. Dijet Mass reconstruction • Results for plot: • chi-square: 12.06 • p-value: 0.8829 • ndf: 19 • chi/ndf: 0.6347

  18. Closest pTbjet reconstruction • Results for plot: • chi-square: 8.373 • p-value: 0.93697 • ndf: 16 • chi/ndf: 0.5233

  19. New Event Selection Verification

  20. Linear Fit To Mean Values y(0): 0.0121648±0.00477388 slope: 0.927763±0.00910238 chi2: 7.63631 NDF: 7

  21. Linear Fit To All Fractions y(0): 0.00762894±0.00158121 slope: 0.935856±0.00280988 chi2: 42.6259 NDF: 8998

  22. MT Plots

  23. Function Fits of QCD Templates Mean: 171.283 ± 5.986

  24. 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

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