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Recent results from TEVATRON

Recent results from TEVATRON. Yuji Takeuchi (Tsukuba) for CDF and DZero collaborations 16 th YKIS Conference Progress in Particles Physics 2008 Feb. 18 th , 2009. Contents Latest Results from ∫ Ldt~3fb -1 Top quark Search for SM Higgs. Tevatron Run II Still at the Energy Frontier.

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Recent results from TEVATRON

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  1. Recent results from TEVATRON Yuji Takeuchi (Tsukuba) for CDF and DZero collaborations 16th YKIS Conference Progress in Particles Physics 2008 Feb. 18th, 2009 • Contents • Latest Results from ∫Ldt~3fb-1 • Top quark • Search for SM Higgs

  2. Tevatron Run IIStill at the Energy Frontier Chicago CDF D0 TEVATRON MAIN INJECTOR • Tevatron: • The world's highest-energy particle collider • Proton-antiproton collisions at √s = 1.96 TeV • Tevatron is performing really well: • Reach 6 fb-1 and 7~8 fb-1 expected by the end of 2009.

  3. CDF: 8 layer silicon vertex detector 8 super layer drift chamber 1.4T solenoid Good particle identification (K,p) Central/Wall/Plug calorimeters Scintillator+drift chamber muon detectors DZero: 8 layer silicon vertex detector 16 layers scintillating fibers 2T solenoid Central/Endcap calorimenters 1.8T toroid 3 layer muon scintillator + drift tubes (Extended muon coverage) CDF/DZero

  4. Tevatron Status • Continually establishing new records! • Peak luminosity ~3.5×1032 cm-2 s-1 • Weekly integrated luminosity 78 pb-1 • Annual integrated luminosity 1.8 fb-1 (US FY 2008) • Avarage pbar accumulation rate • 21×1010 pbar/ hour • Very stable operation • Maximizing integrated luminosity • 10 weeks shutdown in 2009 summer

  5. Integrated Luminosity FY08 FY09 • Integrated luminosities for each US FY • Extrapolation for FY2009: ≳ 2 fb-1 FY 2009

  6. 8.75 fb-1 7.29 fb-1 Highest Int. Lum Lowest Int. Lum Tevatron Prospects FY2010 Fermilab plans to run (if budget allows) and CDF/DZero are ready • Another 2 fb-1, total ~9 fb-1 FY2009 Run continues ~2 fb-1, total ~7 fb-1 Shutdown : 10 weeks from June 1 FY10 start FY09 start ~ 1.8 fb-1 delivered in FY08 FY08 start

  7. Top Quark Physics

  8. Top Pair production Dominant process 10%~20%

  9. Top Pair Signature • All Hadronic • 6jet(2bjet) • Lepton+Jet • 1lepton • 4jet(2bjet) • MET • Dilepton • 2 lepton • 2 bjet • MET Categorize ttbar events into 3 decay types according to W decay mode Top quark decays as a naked quark • Information on spin polarization and momentum is directly transfered to decay products

  10. Top Pair Production Cross-section • Now better than theoretical uncertainties • Luminosity is dominant source of uncertainty

  11. (ttbar)/(Z) • The total uncertainty is decreased by 10% by taking the ratio of the top pair to the Z cross sections +

  12. Top Quark Mass Goal before Run-II started : 3 GeV/c2 with 2 fb-1 Now better than 1%

  13. Matrix Element Method Use information on leptons and jets maximally in-situ Wjj JES calib. JES (jet energy scale) calibration using di-jet invariant mass from W Incorporate JESinto likelihood function L(Mt)→L(Mt,JES) Turn JES systematics into statistics Reduced with statistics of top events Two Breakthroughs in Top Mass Measurements Observables Matrix element with a given top mass gives p.d.f. of observables Mjj→MW Likelihood function of top mass for a given set of observables

  14. Top Mass Measurement World Best. Better than 1%

  15. W Helicity • Information on t-W-b Vertex • Really V-A? • Really W boson? In the standard model

  16. W HelicityMeasurements • Results support V-A coupling on t-W-b vertex so far

  17. Search for anomalous top quark couplings at DZero

  18. Measurement of dσ/dMtt at CDF Singular Value Decomposition (SVD) of the response matrix κ/MPl > 0.16 at the 95% CL

  19. Single Top Production • Cross-section ∝ |Vtb|2 • No need to assume unitarity of CKM matrix nor three generations of quarks • On the assumption of CKM unitarity: Vtb = 0.99 • 3 generations: Can be derived from Br(t→Wb) • Important to understand bkg of WH event for low mass higgs (mH<130 GeV) • Benchmark of higgs search in WH WH :Single Top~1:10 S-channel t-channel

  20. CDF is now preparing combined results for 3.2fb-1 Single Top Summary

  21. Single Top Measurement with ME Technique Signal region

  22. Single Top Prospects • Expected uncertainty on Vtb as a function of ∫Ldt • Uncertainties arise from • Experiment • Cross-section dependence on Mt • Factorization and Renormalization scales • Parton distribution functions • as

  23. W Boson Mass Prospects

  24. W Boson Mass

  25. W Boson Mass World average : MW = 80.398± 0.025 GeV/c2 CDF: ΔMW=0.048 GeV/c2 (L=200pb-1)

  26. W Boson MassUnderstanding the detector Instantaneous luminosity dependence Bremsstrahlung tail

  27. W Boson Mass Prospects • Single experiment sensitivity better than the current world average expected • Will significantly improve constraint on the Higgs boson mass

  28. Constraining the Higgs boson mass

  29. SM Higgs Search

  30. Higgs Cross-section and BR High mass Higgs region: mH>135 GeV/c2 H → WW dominant decay. Gluon fusion production search (gg → H). Low mass Higgs region: mH<135 GeV/c2 H → bb dominant decay. Search for associated W/Z production.

  31. CDF: Updated on Nov 7, 2008 Combined result of NN and ME+BDT Improved by 15% Limit/SM < 4.8 @115 GeV/c2 DZero: Updated on Feb 5, 2009 Limit/SM < 6.7 @115 GeV/c2 WHlbb

  32. DZero: Updated on Aug 2, 2008 New WH lbb result NOT included CDF: Updated on Jan 16, 2009 Updates since last summer WHlbb WH WWW ZH llbb Combined Limits ZHllbb WHWWW WHlnbb

  33. Higgs Exclusion @ Tevatron CDF+DZero combination Updated on Jul 30, 2008 • One mass, 170 GeV, excluded @ 95% CL • A 15 GeV window [162:177] excluded @ 90% CL

  34. Projections • CDF+DZero projections assuming they perform the same • Possible improvements: • Acceptance, Analysis method, jet/MET resolutions, ... • Good possiblity to see 3 evidence to a Higgs of 160 GeV/c2

  35. Conclusion • Tevatron is operating well. Better than ever! • CDF and DZero experiment are ready to run FY2010. ∫Ldt ~ 9 fb-1 is expected. • Top quark properties are being measured more and more precisely. Mass precision is now less than 1%. Top quark properties are consistent with SM so far. • We are sensitive to a Higgs of 160 GeV/c2. • Stay tune for interesting results with ≳ 3fb-1 in 2009!

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