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ttbar  τ + jets : Update on QCD Estimation

ttbar  τ + jets : Update on QCD Estimation. William Edson SUNY at Albany. Fit Selection Results. New Results for Fit: Signal Fraction: 0.691497±0.0411817 Chi2: 28.25 Meas. Used: 31 σ : 166.798±9.93353. New Corrected Results: Signal Fraction: ± 0.0411817 σ : ± 9.93353

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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. Fit Selection Results • New Results for Fit: • Signal Fraction: 0.691497±0.0411817 • Chi2: 28.25 • Meas. Used: 31 • σ: 166.798±9.93353 • New Corrected Results: • Signal Fraction: ± 0.0411817 • σ: ± 9.93353 • Correction Systematic: ±

  3. Systematics Contd.

  4. Top Mass

  5. MC Generator 1.1)fullsim mc11c POWHEG+fPythia sample 117050 (SYST_Full_117050) and MC@NLO+fHerwig sample 105200 (MC@NLO(105200)) 1.2)fullsim mc11c POWHEG+fPythia sample 117050 (SYST_Full_117050) and the fullsim mc11c ALPGEN+HERWIG samples (AlpHerwig(baseline)) 1.3) AtlFast2 mc11b POWHEG+fPythia sample 117050 (SYST_AtF_117050) POWHEG+fHerwig sample 105860 (SYST_AtF_105860)

  6. Back-up

  7. QCD Template: Correlation Plots

  8. Oddity? MET Dijet Mass

  9. Oddity? MET Dijet Mass

  10. QCD Bin/Range Range increases/decreases in steps of 20GeV Bin amount increases/decreases in steps of 5

  11. Y(0): -0.186462 ± 0.0013857 Slope: 1.23971 ± 0.00246245 Chi2: 32.7364 NDF: 8998 Linearity Testto All Values

  12. Linearity Testto Means Slope: 1.23772 ± 0.0351884 y-intercept: -0.184483 ± 0.0198016 Chi2: 0.00520053 NDF: 7

  13. Mean Values of Ensemble Fits

  14. Adjust Range for Linear Fit?

  15. MC Tau Plots MC Tau Children Count MC Tau Count MC Tau Children pdgID LeptonicpdgID values: e → 11, μ → 13, τ → 15

  16. MT Signal vs Control vs MC Backgrounds Samples Normalized to Own Integrals Samples Normalized to Sum of Integrals

  17. Fits/Hists for Ensemble Tests

  18. Cutflow • C0: GRL • C1: Trigger • C2: Primary vertex with ntracks > 4 • C3: Electron/muon overlap • 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

  19. 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

  20. 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

  21. Highest pTbjet reconstruction • Results for plot: • chi-square: 9.818 • p-value: 0.7753 • ndf: 14 • chi/ndf: 0.7012

  22. 2nd Highest pTbjet reconstruction • Results for plot: • chi-square: 13.66 • p-value: 0.5517 • ndf: 15 • chi/ndf: 0.9107

  23. Dijet Mass reconstruction • Results for plot: • chi-square: 15.47 • p-value: 0.6297 • ndf: 18 • chi/ndf: 0.8594

  24. MET • Results for plot: • chi-square: 15.87 • p-value: 0.1971 • ndf: 12 • chi/ndf: 1.323

  25. Closest pTbjet reconstruction • Results for plot: • chi-square: 14.39 • p-value: 0.2123 • ndf: 11 • chi/ndf: 1.308

  26. New Event Selection Verification (Only uses MC so Excludes QCD)

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