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ttbar  τ + jets : Update on QCD Estimation

ttbar  τ + jets : Update on QCD Estimation. William Edson SUNY at Albany. No MET Fit Selection. Results for Fit: Signal Fraction: 0.847182±0.0634855 Chi2: 46.8597 Meas. Used: 57 σ : 208.927±15.656pb Ensemble Results: Mean: 0.760173±0.00269476 chi2: 11.5963.

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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. No MET Fit Selection • Results for Fit: • Signal Fraction: 0.847182±0.0634855 • Chi2: 46.8597 • Meas. Used: 57 • σ: 208.927±15.656pb • Ensemble Results: • Mean: 0.760173±0.00269476 • chi2: 11.5963

  3. Using Serban’s Suggestion of Randomizing Full Data Histogram mean: 0.584753±0.00156137 sigma: 0.0490295 Chi2: 8.17953 NDF: 12

  4. Using Brad’s Suggestion of Using Random Filled TFunction as QCD Template During Fitting Process mean: 0.944558±0.00105631 sigma: 0.0327505 Chi2: 14.6119 NDF: 7

  5. Comparison of Ensemble Data to Real Data Highest pTbjet Second pTbjet

  6. Comparison of Ensemble Data to Real Data Dijet MET

  7. Comparison of Ensemble Data to Real Data Closest Top Mass Reconstruction

  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. Fit With Only 1 Histogram • Highest: • Signal Fraction: 0.796408±0.130703 • Chi2: 15.64128 • 2ndbjet: • Signal Fraction: 0.806464±0.101722 • Chi2: 19.81387 • Dijet: • Signal Fraction: 0.941796±0.0986423 • Chi2: 10.4168 • MET • Signal Fraction: 0.620279±0.044591 • Chi2: 20.35018

  12. New Fits for Ensemble Tests

  13. 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

  14. 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

  15. 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

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

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

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

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

  20. New Event Selection Verification

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

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

  23. MT Plots

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

  25. 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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