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Recent CDF B Results

Recent CDF B Results. KISTI seminar Aug 2 2007 Daejung Kong, KNU. Tevatron. Accelerator delivers. Accelerator & CDF performance. 3.0 fb -1 delivered 2.5 fb -1 to tape. Instant L ~ 2.9 x10 32 CDF II accumulated data of 3.0 fb -1 CDF Detector performs well, including silicon detectors

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Recent CDF B Results

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  1. Recent CDF B Results KISTI seminar Aug 2 2007 Daejung Kong, KNU

  2. Tevatron

  3. Accelerator delivers.. Accelerator & CDF performance 3.0 fb-1 delivered 2.5 fb-1 to tape • Instant L ~ 2.9x1032 • CDF II accumulated data of 3.0 fb-1 • CDF Detector performs well, including silicon detectors • Expect 4~6 fb-1 more by 2009~2010.

  4. CDF Detector • Solenoid • 1.4Tesla • Silicon Tracker • || < 2 • svertex ~ 30 mm • Central Outer Tracker (COT) • 96 layers drift chamber, up to ||~1 • sPT/PT~ 0.15% PT • Particle ID with dE/dx • Time of Flight • Particle ID of low momentum tracks • Muon chamber • 4 layers drift chamber outside the calorimeter • || < 1

  5. CDF Collaboration • 60 Institutes • 500 people

  6. Crossing: 396 ns, 2.5 MHz Level 1: hardware Electron, Muon, track, missing Et 15-20kHz (reduction ~x200) Level 2: hardware Cal. Cluster, jet finding, Silicon track 300-350 Hz (reduction ~x5) Level 3: Linux PC farm ~ Offline quantities 50-70 Hz (reduction ~ x6) CDF Trigger System Overview

  7. QCD b-bbar dijet production cross section Z+jets cross section measurement Z b-bbar Dijet production cross section measurement B Physics Spectroscopy Lifetime measurements: B+, B0, Bs andLB Rare decay searches: B+m+m-K+, B0m+m- K*, Bsm+m- Bhh New Phenomena Search for New Particles Coupling to Z+jets (b'->Z+b) SUSY trilepton combined limit High-mass dielectron (Z’ search) Top Top mass in all-jets channel Production cross section Search for W' using the single top sample Top Production Mechanism (gg vs qq) Top Charge EWK Observation of WZ production Evidence for ZZ production W mass, width Higgs HttSUSY Higgs HWW ME-based analysis ZHllbb 2D-NN and MET fitter analysis Hot Physics Programs

  8. MSSM Higgs Search A 2 Sigma Excess

  9. W, Top, Indirect Higgs World’s best measurements! MH can be constrained by precisely measuring MW and Mtop : MH = 85+39-28 GeV (EWWG) (MH < 166 (95% CL))

  10. B Physics & B Triggers CDF: , |y| < 1 b Production cross section: PRD71, 032001 (2005) Large Cross section ! • Heavy states produced • B0, B+, Bs, Bc, b, Σb, b • Di-muon trigger(lifetime, mass, branching ratios, ∆G/G) • pT() > 1.5 GeV/c, within J/y mass window • Two displaced-tracks trigger(branching ratios, mixing) • pT > 2 GeV/c, 120 m ≤ d0≤ 1 mm,Lxy> 200 m, S pT > 5.5 GeV/c • Lepton + displaced-track trigger(lifetime, fbaryon, mixing) • pT(,e) > 4 GeV/c, 120 m ≤ d0≤ 1 mm, pT > 2 GeV/c

  11. B Physics Programs • Bs Mixing • Bc Mass • DGsands • B  hh’ • B mm, B mmh • Orbitally excited B hadron • Observation ofSb • Prospects

  12. BsOscillation D0 has a limit 17<Dms<21 ps-1 (90% CL) CDF, with 1fb-1 presents Observation of Bs Oscillations PRL 97, 242003 2006 Dms=17.77±0.10(stat)±0.07(syst) ps-1 : > 5sobservation Same data set used for previous (spring 06) limit Improved selection Improved analysis technique A lot of efforts

  13. Neutral B meson oscillation Lattice QCD, hep/lat-0510113 • The eigenstates of the weak interaction are different from those of the strong interaction  mixing in quark families • Oscillation frequenciesDmd and Dmsdetermine poorly known Vtd and Vts • Theoretical uncertainties reduced in ratio, 11%  3% STRONG (MASS) EIGENSTATES WEAK (FLAVOR) EIGENSTATES

  14. DGsands • Light and Heavy Bs mass eigenstates Dms MH– ML DGGL–GH • The mass eigenstates are expected to be almost pure CP eigenstates • The CP violating mixing phase is predicted to be s = (4.2  1.4) x 10-2 A.Lenz & U.Nierste, hep-ph/0612167 • New Physics may alter s leading to a reduction of the observedDGs DGs = DGsSM x |cos s|

  15. DGsandsin Bs J/ • Bs J/  J/m+m-,  K+K- • Fit time dependent angular distributions, mass and lifetime • direct constraint ons • 4-fold ambiguity,sand(p - s) the sign of sinsis reversed with the simultaneous reversal of the signs of the cosines of the CP-conserving strong phasesd1andd2 consistent with the SM prediction

  16. Bc Mass World’s best measurements!

  17. B→ hh =arg(Vub) Penguin Tree • a useful tool for probing CKM • sensitive to the New Physics contributions • in the Penguin diagrams • sensitive to New Physics effects via anomalies in ACP

  18. B→ hh 7000 Signal events S/B  8.3 at the peak Signal composition is determined with a Likelihood Fit, combining information from kinematics (mass and momentum) and particle identification (dE/dx).

  19. Search for Bs/d→ • In the SM, B→ heavily suppressed (need FCNC) expectation: • Bd→ further Cabbibo-suppressed • Expect to see nothing, if something seen  new physics A.J. Buras, Phys. Lett. B566, 115 (2003) In SUSY, potentially much larger BR

  20. Apply Selection • Observation in agreement with background expectation • Set limits

  21. Results Bs/d→ Dominant uncertainty sources • World best limit, compare • Babar (hep-ex/0408096, 110 fb-1 ) • BR(Bdmm) < 8.3 ∙ 10-8 @ 90% C.L.

  22. Search for B→h • Non-resonant decays B →h via box or penguindiagrams  new physics may be observable through interference withSM amplitudes • Already observed (BaBar, Belle): • Bu →K • Bd →K* • Missing: • Bs → • prediction: BR(Bs)=1.6x10-6 PRD 73, 092001 (2006) PRL 96, 251801 (2006) J. Phys. G 29, 1103 (2003)

  23. Observations B→h

  24. Rranching ratio BR(B+→ K+) = [0.72 ± 0.15(stat.) ± 0.05(syst.)]x10-6 BR(B0→K*) = [0.82 ± 0.31(stat.) ± 0.10(syst.)]x10-6

  25. B baryon Spectroscopy * Orbitally excited B0 mesons (L=1, B0**) * Orbitally excited B0s mesons (L=1, Bs**) * New bottom baryons (buu and bdd), part of a new I-tripletSb

  26. B Trigger (dimuon, hadronic) J/y trigger Hadronic B trigger B+ decays: Lb decays 2.8 K events Lb→Lcp 532 events (not used for Sb) Lb-> J/y L

  27. Bs** only 370 fb-1, but includes a sample of B+→D0p+collected with the SVT: Natural width fixed 16 MeV (theory) Detector resolution ~ 3-4 MeV

  28. Motivation, Sb(*) ± About 2.8K eventsLb→L+cp-L+c→pK-p+in the hadronic trigger. The plot shows a fit to the Lbmass in this sample, together with predicted backgrounds. Sbcandidates are formed by adding a “soft”p±. (no pT cut) .

  29. Sb(*) ± Lc+ Lc+ Lb0 Lb0 p- p- Sb(*)+ Sb(*)- p+ p- Sb+ (buu) → Lbp+ Sb- (bdd) → Lbp- Sb+ (buu) → Lbp- Sb- (bdd) → Lbp+ I-spin partners, not antiparticles! Pions have same sign Sb(*)- Pions have opposite sign Sb(*)+ Region 30 < Q < 100 MeV/c2 is kept blind in this analysis. Monte Carlo and Sidebands used to optimize impact parameter significance cuts on the soft pion, cosq* (ps)cuts, andpT(Sb) MC used to evaluate theDM resolution (checked with D*)

  30. Result, Sb(*) ± p-value for the four-peak fit to be due to a deviation of NULL hypothesis corresponds to a significance > 5.2s

  31. Observation of Sb June 2007

  32. D0 Mixing • Mixing observed in K0, Bd and Bs, but not yet in D0 • Charm mixing is slower than B or K mixing • Use D*  D0p+to tag the original flavor as D0 or anti-D0 • D0 K-p +, Cabibbo Favored (CF) • D0 K+p -, Doubly Cabibbo Suppressed (DCS)

  33. D0 Mixing at B Factories • Mixing parameter • y = DG/ 2G • x =Dm / G • y’ = ycosd–xsind • d= strong phase difference between CF and DCS amplitudes • mixing parameter yCP = t(D0 K-p+) / t(D0 K+K-) • in CP conservation limit yCP = y • Belle (hep-ex/0703036) • 540 fb-1 • yCP = 1.31 ± 0.32 (stat) ± 0.25 (syst) % • more than3sabove zero • BaBar (hep-ex/0703020) • 384 fb-1 • y’ = 0.97 ± 0.44 (stat) ± 0.31 (syst) % • 3.9sdeviation from zero • Evidence for D0 mixing

  34. Latest B result  LP07’ • Direct measurement ofs • measure time dependent CP asymmetry in Bs J/  • ACPmix from Bs J/  • D0 mixing, D0 direct CP asymmetry

  35. Summer Shutdown 2007 Start date : Aug 5, 2007. Duration : 10 week (+ 2 weeks of TeV studies) ISL cooling PMT, Online • Aug 5 Beam off • Aug 6 ~ Sep 24 Detector Open ~ works • Oct 1 Close up • Oct 8 Detector Checkout • Oct 15 ~ Oct 22 TeV Startup • Oct 29 Collisions

  36. CDF & Korean Activities CDF Korea group CDF Publications * ~3% of CDF collaborators • CDF Korea group contributes to some essential aspects of CDF operation • Korea group’s publications ~10% of CDF papers in 2006

  37. CDF Computing Farm

  38. Summary • The interest of phyiscs program stays in the combination of an Tevatron performance & CDF detector • Tevatron experiments provide a lot of opportunities to study Heavy quark physics • CDF B physics is complimentary to B factories and/or provides new search & new physics • More and more challenging analysis are being performed

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