1 / 30

ttbar  τ + jets : Update on QCD Estimation

ttbar  τ + jets : Update on QCD Estimation. William Edson SUNY at Albany. Only MET and Dijet Mass Fit Selection. New Results for Fit: Signal Fraction: 0.664442±0.0418289 Chi2: 29.953 Meas. Used: 31 σ : 170.884±10.7578. New Corrected Results: Signal Fraction: 0.685204± 0.0418289

caraf
Download Presentation

ttbar  τ + jets : Update on QCD Estimation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

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

  2. Only MET and Dijet Mass Fit Selection • New Results for Fit: • Signal Fraction: 0.664442±0.0418289 • Chi2: 29.953 • Meas. Used: 31 • σ: 170.884±10.7578 • New Corrected Results: • Signal Fraction: 0.685204± 0.0418289 • σ: 176.223 ± 10.7578 • Correction Systematic: ±3.87838

  3. Cutflows

  4. Systematics Contd.

  5. Top Mass Original kfac/σ(FE) from TopMC11 twiki Correction using Ref σ’s Using kfac/σ(FE) from 105200

  6. 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)

  7. QCD Template: Divided Control Region

  8. QCD Template: Correlation Plots

  9. Oddity? MET Dijet Mass

  10. Oddity? MET Dijet Mass

  11. Back-up

  12. for (unsigned inttfj = (tau_matched.size() - 1); tfj > 0; tfj--) { try { int REFN1 = tau_matched.at(tfj).entry(); int REFN2 = tau_matched.at(tfj-1).entry(); if( (physics->tau_BDTJetScore->at(REFN1)) > (physics->tau_BDTJetScore->at(REFN2))) { save = tau_matched.at(tfj); tau_matched.at(tfj) = tau_matched.at(tfj-1); tau_matched.at(tfj-1) = save; } } catch (conststd::out_of_range& C12_2){ std::cerr << endl << "C12.2: OUT OF RANGE ERROR: " << C12_2.what() << endl; EMERXIT = 12; continue; } }

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

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

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

  16. Mean Values of Ensemble Fits

  17. Adjust Range for Linear Fit?

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

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

  20. Fits/Hists for Ensemble Tests

  21. 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

  22. 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

  23. 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

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

  25. 2nd Highest pTbjet reconstruction • Results for plot: • chi-square: 13.66 • p-value: 0.5517 • ndf: 15 • chi/ndf: 0.9107

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

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

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

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

More Related