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Hot Topics from CDF and D0 D.Glenzinski Fermilab ICHEP 2006 01-August

Hot Topics from CDF and D0 D.Glenzinski Fermilab ICHEP 2006 01-August. Chicago . Wrigley Field. pp collider at world’s highest energy E cm = 2 TeV Run-I 1990-1995 (110 pb -1 /experiment) Run-II 2001-2009 (6-8 fb -1 / exp expected) Performing excellently.

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Hot Topics from CDF and D0 D.Glenzinski Fermilab ICHEP 2006 01-August

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  1. Hot Topics from CDF and D0 D.Glenzinski Fermilab ICHEP 2006 01-August

  2. Chicago  Wrigley Field • pp collider at world’s • highest energy • Ecm = 2 TeV • Run-I 1990-1995 • (110 pb-1 /experiment) • Run-II 2001-2009 • (6-8 fb-1 / exp expected) • Performing excellently CellularField Tevatron CDF DØ Main Injector Fermilab Tevatron D.Glenzinski, Fermilab

  3. ICHEP-04 Results : 200 pb-1 • ICHEP-06 Results : 1000 pb-1 (per experiment) Delivered Luminosity pb-1 200220032004 2005 2006 Tevatron Run-II • Data set has doubled every year D.Glenzinski, Fermilab

  4. Experiments: CDF • Features: • Precision silicon vertexing • Large radius drift chamber • (r=1.4m) • 1.4 T solenoid • EM+HAD Calorimetry • muon chambers • (|h| < 1.1) • Particle Identification D.Glenzinski, Fermilab

  5. Experiments: CDF D.Glenzinski, Fermilab

  6. Experiments: DZero (D0) • Features: • Precision silicon vertexing • Outer Fiber Tracker • (r=0.5m) • 2.0 T solenoid • EM+HAD Calorimetry • muon chambers • (|h| < 2.0) D.Glenzinski, Fermilab

  7. Experiments: D0 D.Glenzinski, Fermilab

  8. Tevatron Results Published • From Run II: • 41 Physics publications by CDF • 33 Physics publications by D0 • In 2005: 1 Tevatron publication every 7 days • So far in 2006 • Each experiment has ~15 Published+Accepted, plus another ~15 submitted analyses • At this conference • A total of 39 talks in parallel sessions D.Glenzinski, Fermilab

  9. Tevatron Results at ICHEP-06 • Parallel Speakers • F.Canelli, A.Hocker, J.Nielsen, C.Hill, K.Hatakeyama, A.Kupco, M.Sanders, C. Schwanenberger, S.Blessing, M.Verzochi, G.Bernardi, D.O’Neil, D.Wicke, T.Moulik, M.Strauss, G.Borrisov, A.Nomerotski, S.Anderson, W.Taylor, E.Kajfacz, H.Greenlee, T.Hebbeker, P.Savard, I.Gorelov, B.Kilminster, E.Lipeles, M.Lancaster, A.Kraan F.Wuerthwein, P.Busey, R.Field, S.Giagu, S.Farrington, L.Pinera, M.Kreps, Y.S.Chung, A.Hamilton, A.Pronko, W.Wagner • Plenary Speakers • R. Barlow “Rare B and Tau Decays” • E. Gallo “Beyond the Standard Model (Experiment)” • D. Wood “Precision Electroweak Results” D.Glenzinski, Fermilab

  10. with 1 fb-1 1.4 x 101 1 x 1011 6 x 106 6 x 105 14,000 5,000 100 ~ 10 In 1 fb-1 Production cross-section (barns) Tevatron Physics Program (b) • QCD • Heavy Flavor • Electroweak • Top Quark • New Phenomena • QCD • Heavy Flavor • Electroweak • Top Quark • New Phenomena I Will discuss only a few of the “Hottest” Results D.Glenzinski, Fermilab

  11. Hot Topics (Doug’s Opinion) • Latest Bs Mixing Results • Latest Top Mass Results • Latest New Phenomena Results • Our raison d’etre • Unique to Tevatron Program • Have significant impact D.Glenzinski, Fermilab

  12. Bs Mixing • D0 Results using 1 fb-1 • CDF Results using 1 fb-1 D.Glenzinski, Fermilab

  13. Bs Mixing: Motivation • Bs particles can change into their anti-particles • The rate at which BsBs oscillate : ms • Important consistency check of CKM quark-mixing Matrix in Standard Model: ms ~ Vts D.Glenzinski, Fermilab

  14. Bs Mixing: Basics • Probability that Bs at t=0 decays as Bs at time t • Experimentally, measure Asymmetry as a function of proper decay time D.Glenzinski, Fermilab

  15. Bs Mixing: Basics Actual Perfect Detector D.Glenzinski, Fermilab

  16. determined using “Flavor Taggers” D2 determined by reconstruction of Bs at decay NB determined by reconstruction of Bs at decay t Bs Mixing: Ingredients • For each event we need to determine • Bs or Bs at production? • Bs or Bs at decay? • Proper decay time mixed or unmixed? D.Glenzinski, Fermilab

  17. CDF 1 fb-1 Events / 0.001 GeV/c2 Ds mass [GeV/c2] Bs Mixing: 1) Identify Sample • Bs is reconstructed via semi-leptonic decays D.Glenzinski, Fermilab

  18. CDF 1 fb-1 Mass of Bs (GeV/c2) Bs Mixing: 1) Identify Sample • Bs reconstructed via hadronic decays: unique to CDF D.Glenzinski, Fermilab

  19. # reconstructed Bs D0 CDF Semi-leptonic 36,500 37,000 Hadronic - 3,600 Bs Mixing: 1 fb-1 Yields Next, determine proper decay time… D.Glenzinski, Fermilab

  20. + + Ds- LT Bs decay vertex production vertex Bs Mixing: 2) Proper Decay Time • Determine proper decay time from final state: determined from Monte Carlo (MC) simulation D.Glenzinski, Fermilab

  21. Hadronic Decays <> ~ 25 m Semileptonic Decays <> ~ 45 m Bs Mixing: Decay Time Resolution • Hadronic decays have excellent proper time resolution proper decay time resolution () / cm D.Glenzinski, Fermilab

  22. b and b hadronize independently Bs K- B) Same Side Tag (SST) Infer production flavor knowing flavor of fragmentation tracks b b Bd, B+, b, … Bs Mixing: 3) Flavor Tagging • B-Hadron Production at the Tevatron • Predominantly produced in bb pairs A) Opposite Side Tag (OST) Infer production flavor knowing flavor of the other b in the event D.Glenzinski, Fermilab

  23. Bs Mixing: 3) Flavor Tagging • Flavor Taggers are characterized by: • The effective statistics depend on these terms: D.Glenzinski, Fermilab

  24. For OST Compare tagger decision to known flavor using fully reconstructed B Bs For SST Determined from MC. Validate MC using reconstructed B Dilution [%] Bd, B+, b, … Bs Mixing: Flavor Tagging • Determining the dilution: B- + D.Glenzinski, Fermilab

  25. D2 D0 CDF OST 2.5% 1.5% SST - 3.5% Total 2.5% 5.0% Bs Mixing: Flavor Tagging Performance D.Glenzinski, Fermilab

  26. Bs Mixing: Sensitivity • “Sensitivity” = expected 95% CL upper limit on ms • Determined from data ms Sensitivity (ps-1) World 2006: 18 D0 2006: 17 CDF 2006: 25 D.Glenzinski, Fermilab

  27. Bs Mixing: Measuring ms • Look for evidence of Bs mixing using Amplitude Scan • Fourier transform to frequency domain • Determine amplitude for fixed ms • Scan ms : Amplitude = 1 at true ms, 0 otherwise D.Glenzinski, Fermilab ms (ps-1)

  28. (Aug-06) 1 fb-1 1 fb-1 New! 50% more Bs PRL 97 (2006) 021802 8% probability Random tags would look as significant Bs Mixing: D0 Results (Mar-06) 17< ms < 21 ps-1 @ 90% CL D.Glenzinski, Fermilab For more details see the talk by T.Moulik.

  29. +0.33 -0.18 Bs Mixing: CDF Results (Apr-06) CDF 1fb-1 hep-ex/0606027 (accepted by PRL) ms = 17.31 (sta)  0.07 (sys) 0.2% probability Random tags would look as significant D.Glenzinski, Fermilab For more details see the talk by S.Giagu.

  30. Bs Mixing: Constraints • measured ms agrees • with SM prediction • relative precision of • measured • ms)/ms = 1.5% • md)/md = 1.0% • precision of measured • ms is statistics limited • (syst)/ms < 0.5% D.Glenzinski, Fermilab

  31. Bs Mixing: Constraints • use measured ms to • constrain CKM • agrees with SM prediction • x5 more precise than • previous determination • limited by Lattice uncertainty D.Glenzinski, Fermilab

  32. Bs Mixing: Constraints D.Glenzinski, Fermilab For latest fit results see talks by S.T’Jampens, V.Vagnoni,and M.Bona

  33. Bs Mixing: New Physics Constraints • Use ms and CP violation in Bs sector to constrain New Physics contributions • Bs sector largely unexplored • Bs sector largely independent of Bd sector • Bs sector more sensitive than Bd sector • New Physics can affect ms and CP phase () D.Glenzinski, Fermilab

  34. Constraint from ms, s, ACH combined NP(Bs) / degrees X dark: 68% light: 95% SM Bs Mixing: NP Constraints • Recall For decails see: hep-ph/0012219, hep-ph/0406300, hep-ph/0605028, talks by S.T’Jampens and V.Vagnoni D.Glenzinski, Fermilab

  35. 1 fb-1 SM New! Bs (rad) Bs Mixing: NP Constraints • CDF and D0 can • also constrain  • D0 combines 3 • measurements • to get first constraints • precision of all 3 are • statistics limited • more data to come • CDF + D0 • direct CP using flavor • tagged decays D.Glenzinski, Fermilab For more details see the talk by G.Borissov.

  36. Top-Quark Mass • D0 Results using 0.4-1 fb-1 • CDF Results using 1 fb-1 D.Glenzinski, Fermilab

  37. t t b b t b t t W H W H Z W Top Mass: Motivation • Mt is a fundamental parameter of the Standard Model • Since Mt is large, quantum loops involving top quarks are important to include when calculating precision observables (e.g. sin2w, Rb, Mw,…) • Within SM, particularly important to help constrain MH D.Glenzinski, Fermilab

  38. Top Mass: Motivation • Mt important input for any model trying to describe high energy particle physics • In MSSM at tree level: Mh<Mz (very excluded) w/ Mt loop corrections: Mh < 135 GeV • Mt impacts soft-SuSy breaking phenomenology • Mt plays critial role in verifying gauge unification through RGEs • Precision Mt crucial to understanding underlying theory of HEP, whether SM or SuSy or … D.Glenzinski, Fermilab

  39. 15% Top Mass: Basics • Top quarks predominantly produced in pairs via the strong interaction • Production cross-section:  ~ 7 pb at Tevatron 85% D.Glenzinski, Fermilab

  40. “Di-Lepton” “Lepton+Jets” “All Jets” Top Mass: Basics • Because Mt > Mw + Mb, and Vtb>> Vts,Vtd • Final state determined by W decays D.Glenzinski, Fermilab

  41. Top Mass: Basics • We measure Mt in each of these final states • Dilepton (DIL) • Lepton+Jets (LJT) • All Jets (AJT) • Compare across channels for consistency • Combine all channels for improved precision D.Glenzinski, Fermilab

  42. Top Mass: Ingredients • To measure Mt we need to: • Collect top quark sample • Reconstruct observable sensitive to Mt • Unfold experimental effects D.Glenzinski, Fermilab

  43. Top Mass: 1) Collect Sample • Dilepton: ttllbb 2 high energy leptons, missing energy (), 2 jets In 1 fb-1: #signal~50, Purity~65% • Lepton + Jets: ttlqqbb 1 high energy lepton, missing energy (), 4 jets (1 Bjet) In 1 fb-1: #signal~230, Purity~90% • All Jets: ttqqqqbb 6 jets (1 Bjet) In 1 fb-1: #signal~200, Purity~30% D.Glenzinski, Fermilab For more details see talks by C.Hill and D.O’Neil

  44. Top Mass: 1) Collect Sample • cross-sections and kinematics agree with Standard Model D.Glenzinski, Fermilab For more details see talks by D.Wicke, A.Kraan, S.Anderson

  45. Need q q’ b b Lepton  Have Jet 1 Jet 2 Jet 3 Jet 4 Lepton Et Have Jet Energies Need Parton Energies “Jet Energy Scale”(JES) ? Combinatoric Background Top Mass: 2) Event Reconstruction DIL : 2 combinations LJT: 12 combinations AJT: 90 combinations D.Glenzinski, Fermilab

  46. Uncorrected Corrected Monte Carlo Mt = 175 GeV/c2 M(qqb) / GeV/c2 Top Mass: 2) Reconstruction Jet Energy Scale == Absolute Mass Scale • hadronization, • non-linearities, pile-up, • multiple-interactions, • underlying event • From Data and MC • known to ~3% for Mt • jet energies • Leading Run I syst • Reduced in Run II D.Glenzinski, Fermilab

  47. q W q t b Top Mass: 2) Reconstruction • Run II analyses further constrain JES • In-situ constraint possible by comparing observed Mqq to known Mw (in LJT and AJT channels) • with 1 fb-1, reduces (JES) systematic by factor of 2 • (JES) will scale with sample statistics Mqq = Mw D.Glenzinski, Fermilab

  48. true Mt “data” measured Mt Dilepton Channel m(reco) GeV/c2 Lepton+Jets Channel Top Mass: 3) Unfold Exp Effects • Use detailed Monte Carlo to unfold experimental effects and determine Mt from Mreco D.Glenzinski, Fermilab

  49. New! Top Mass: Results (cf. http://tevewwg.fnal.gov) • Excellent results in each • channel • Combine all CDF+D0, • Run-I+Run-II • Account for all correlations • Uncertainty: • Mt(stat) = 1.2 • Mt(JES) = 1.4 GeV/c2 • Mt(syst) = 1.0 Mt determined to 1.2%! Stat+JES scale with sample size D.Glenzinski, Fermilab

  50. LJT AJT DIL Mt (jes) (Signal) (Bgd) (Other) (syst) (stat) (total) 164.5        170.9        174.0        the most precise result in each channel Top Mass: Results (in units of GeV/c2) Jet Energy Scale is leading systematic in all channels uses in-situ JES calibration comparing Mqq to Mw Composition, Normalization, and Shape MC statistics, Method, B-tagging, etc Single most precise determination ISR, FSR, PDF, NLO effects D.Glenzinski, Fermilab For more details see talk by F.Canelli

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