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Steve Nahn-Yale University/CDF Ambassador for the CDF and D Ø Collaborations

B Physics at the Tevatron. Steve Nahn-Yale University/CDF Ambassador for the CDF and D Ø Collaborations. Mandate: “..The invited session talks are 30+6 minute review talks designed to highlight and advertise the many short talks in the contributed sessions” “many”  30 in this case!. Plan.

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Steve Nahn-Yale University/CDF Ambassador for the CDF and D Ø Collaborations

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  1. B Physics at the Tevatron Steve Nahn-Yale University/CDF Ambassador for the CDF and DØ Collaborations Mandate: “..The invited session talks are 30+6 minute review talks designed to highlight and advertise the many short talks in the contributed sessions” “many”  30 in this case!

  2. Plan • Short Course in Heavy Flavor Physics @ TeV • Excellent intro by P. Burchat in A0 • Heavy Flavor Results Smorgasbord • Production measurements • Decays • Lifetimes and Mixing results presented at APS/DPF `05. • Highlight results presented at APS/DPF `05. • Where other results exist, not discussed • Attempt at equal exposure for each experiment • Details? GO TO THE SESSIONS! other results S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  3. The Tevatron is a Dirty B factory • Wealth of B Physics • Only ~5% reconstructable • Zoo of b hadrons: B0, B+, Bs, Bc, b,  b, B** • But • O(103) higher • Hard to find “other b” • ~ 30% acceptance • Boost not large Lots going on in Si detector S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  4. Both detectors Silicon microvertex detectors Central tracking in Solenoid High rate trigger/DAQ system Calorimeter & muon systems Require all-charged final states CDF silicon detector installation Detectors • DØ • Excellent electron & muon ID • Excellent tracking acceptance • CDF • Particle ID (TOF and dE/dx) • Excellent mass resolution DØ fiber tracker installation S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  5. Datasets • After slow start, Tevatron excelling • dLint/dt increasing • Data on tape: • ~500 pb-1 2002-2004 • ~ +100 pb-1 2005 • DØ: • ~220-500 pb-1 in these results • CDF: • ~240-360 pb-1 in these results S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  6. B y x Triggering: Heavy Flavor  Tape • Hb X(J/  ) • 2 track  matches within m window • Hb lnX • Lepton signature in pT range • Hb hadrons • Displaced tracks and vertex S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  7. Heavy Flavor Analysis • Selection techniques • Quality objects • Kinematics • Consistent vertex structure • Reference channels • Relative Branching Ratios • Calibrate algorithms • Optimize Selection • Simulation • Detector effects • Other resonance pollution • Algorithms • Simultaneous likelihood fits • PID for statistical separation Golden Bs Modes Ds+D++ S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  8. Production of Bc Mesons • Least well known B meson • Theory: Largest mass, shortest lifetime • 20  6 events in Run 1 S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  9. Bc J/l  S J8: CDF: Hartz & Aoki DØ: Ay • B J/ K as reference • Background suppression KEY • Fake J/ or lepton • b [J/] b [ l ] • CDF: separate cross section ratio for l = m ,e • Combined lifetime next • DØ: mass and lifetime in m • Moving to Bc J/ _ S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  10. Something new: X(3872) • Observed by Belle, confirmed by TeV, but what is it? • Charmonium? • DD “molecule”? • Seen in XJ/ at TeV • (2S) J/ is reference channel † Addition of m(J/) by SN S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  11. Further X Studies • DØ: Measure fractional production versus kinematic quantities • Compare with (2S) • “Charmonium”-like • CDF: Examine the m spectrum versus theory • Rules out some, but none perfect S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  12. Other Heavy Flavor Production • B**(L=1) B • B J/K and D modes • Important to understand impact for mixing • Cross section Bl DX • Complement to J / mode • J/ Spin Alignment • Test “Octet” Production model S Z8: CDF Pursley S Z8: CDF Kraus DØ S Z8: CDF Kim S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  13. Heavy Flavor Decays • New Modes • Test against theory predictions • Add statistics for mother particle studies • Help understand background in other analyses • Rare decays limit contributions New Physics • CP Violation in Decay • cf. Babar … S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  14. Plethora of new channels S Z8: CDF Iyutin S Z8: CDF De Lorenzo S J8: CDF Kong • Bs(2S) • BDsD • Bs ~40 events S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  15. Semileptonic decays to excited states • BD**mn • BsDs**mn • Ds**D*KS S Z8: DØ Tsybychev S C8: DØ Rieger S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  16. Rare Decays • FCNC Charm Decays cu • Df  relative to Ds • Precusor to nonresonant study • Bsmm BrSM ~ 10-10 New Physics! • 4.3 ±1.2 expected, 4 seen • Bsmm • Sensitivity: S J9: DØ Casey CDF S J8: DØ Bernhard S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  17. Lifetimes and Mixing • B mixing  CKM • Prereq to Mixing • Test HQE theory C. Tarantino, hep-ph/0310241 Oct 2003 LO NLO Experiment Theory S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  18. S Z8: CDF Miles Clark S U12: CDF Da Ronco S J8: DØ Casey Heavy Flavor Lifetimes • Tevatron Industry • Typically Simultaneous Mass and Lifetime fit S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  19. Example Lifetimes: Bs • DØ BsDsl  • Ds   • Overcome  w/simulation • CDF Bs Ds • Ds   • Trigger Bias S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  20. Bs Lifetime Difference DG S H8: DØ Welty • BsJ/ • B VV, mixture of CP even/odd separate by angular analysis • Combine two-lifetime fit + angular DGs=GH-GL • SM DGs/Gs=0.120.06 (Dunietz, Fleischer & Nierste) • Indirect Measurement of Dms S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  21. Direct B mixing in a nutshell • Measure Asymmetry • Determine “time” of Decay: st= Proper lifetime resolution • measure decay length, apply boost • Sort the mixed from unmixed via b charge at production and decay • S = Signal Yield  efficiency for making a determination • D = “Dilution” = (2P-1); P = Probability of correct assignment S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  22. S H8: CDF Giurgiu and Belloni U 12: DØ Naimuddin and Krop Calibration on Bd • Know the right answer • Tests Fitting Mechanism • Calibrates Tagging • Much higher statistics S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  23. S J8: CDF Giurgiu U 12: DØ Naimuddin/Krop Bs Mixing Results • Amplitude Scan • Fourier Transform into Dm space only floating A • A = 1 for true Dm, 0 else • Limit A+1.645sA = 1 • Sensitivity  1.645sA = 1 • NIM A384(1997) p.491 ff. S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  24. S U12: “Tevatron techniques in B Physics” CDF and DØ Potential in Bs Mixing • Statistics: Ifgain factor of 4 from • Opposite and Same Side Kaon Tagging (CDF), Electron Tagging (DØ) • More Channels, More Luminosity, Smarter Triggers • Multivariate Tagging approach • And If gain 20% on Proper Time resolution • Event By Event Primary Vertexing • Better st understanding 4 Statistics +20% Resolution S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  25. Whew! • Tremendous amount of Heavy Flavor activity going on at the Tevatron • Squeezing Physics from data samples available nowhere else • Manpower limited • Most of the Luminosity still to come • We’re at 0.8, expect >4 fb-1 total • Crucial “Run 2b” upgrades done this fall • CDF: Track Trigger, Displaced Vertex Trigger … • DØ: Inner Silicon Layer, Track Trigger … S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  26. Backup Slides S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  27. Bc J/ • Fully reconstructed • Good mass resolution • Is it significant? • Analysis done “blind” • Loosen cuts, look for partial reconstructed Bc in low mass sideband • compare d0() w.r.t. J/  • See similar excess in B+ S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  28. Pentaquark Production? S Y12: CDF Field • [5 quark bound state]  Baryon-Meson • Observed elsewhere: Can they be seen at TeV? • same trigger/kinematic range as Heavy Flavor • many reference decays cDp m 3.1 GeV/c2 Reference None Seen S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  29. Im Re Standard Model Mixing • In Standard Model, Mixing from CKM matrix • Flavor states not mass eigenstates on the quark level • CP Violation inherent with 3 generations • Comes in through loops, akin to New Physics • Mixing sensitive to other particles in loop s b W t t _ s b _ W _ S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  30. Mixing Channels of interest • Decay chain tags the flavor • Lepton/Pion from b decay • Hadronic Decays • Fully reconstructed  excellent resolution • Trigger on pair of 2 GeV displaced tracks • Semi-leptonic decays • Higher statistics, but miss neutrino • Trigger on 2 GeV displaced track and 4 GeV lepton • Collect multiple Ds decays S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  31. S U12: “Tevatron techniques in B Physics” (Now!) CDF and DØ Candidate (Same) Side Opposite Side Fragmentation track Hb p D Bs K p Ds K Production Flavor • Look at associated particles • Other b decay • Lepton Charge • Charge of B decay products: • Kaon Charge • Nearest charged track • Vacuum gives net charge 0 S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  32. Current World Knowledge • dominated by “B factories” • Designed specifically for this purpose • not accessible at B factories, have world ave. • Limit from and S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

  33. Measuring a limit: Amplitude Scan • msmeasurement is “blinded” • Study all systematics, sensitivity without looking at the answer • Looks like a limit  Amplitude Scan • Fix tagging parameters from from md measurement • Add Amplitude factor to the oscillation term, scan ms space • NIM A384(1997) p.491-505 • Check for md: S Nahn - "B Physics at the Tevatron" APS/DPF 05 Tampa

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