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Selected Results from D Ø and CDF

Selected Results from D Ø and CDF. Don Lincoln Fermilab/D Ø. Topics. Pentaquark searches X(3872) Selected heavy flavor results Selected hard-scatter physics 30+ analyses, 2 experiments No details!. Collision Energy: 1960 GeV Crossing time: 396 ns Design Luminosity:

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Selected Results from D Ø and CDF

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  1. Selected Results from DØ and CDF Don Lincoln Fermilab/DØ

  2. Topics • Pentaquark searches • X(3872) • Selected heavy flavor results • Selected hard-scatter physics • 30+ analyses, 2 experiments • No details! Collision Energy: 1960 GeV Crossing time: 396 ns Design Luminosity: 2 × 1032 cm-2 s-1 Peak Delivered Luminosity: ~1 × 1032 cm-2 s-1

  3. Accelerator Performance • Since early 2002 [DØ]: • Integrated Luminosity delivered: ~600 pb-1 • Recorded ~470 pb-1 • Overall Efficiency ~78% • Recent efficiency somewhat higher. • CDF performance comparable (520/650) • Greater integrated luminosity due to Tevatron effects (+ 10%) • Tevatron off until mid-November

  4. Detector Upgrades • New DAQ • Superconducting Solenoid • Silicon Tracker • Central Fiber Tracker • Upgraded Muon Detector • Upgraded Calorimeter Electronics • New DAQ • New Track Trigger • New Silicon ||<2 • Improved b-tagging • New Drift Chamber • New Plug Calorimeter • Increase acceptance • Upgrade Muon Detectors

  5. CDF Particle ID [TOF] CDF particle ID also includes dE/dx. DØ particle ID separates e, m, g, jets.

  6. Search Modes: • + →Ksop + - •co D*+p(bar) Do+ K- + • 3/2--/o [F] -- L - -p • Rs+ J/p+ l +l - Pentaquark Fest • 5 quark state predictedby Diakonov, Petrov, Polyakov (1997): • 4 quarks + 1 antiquark • Q+ : u u d d s(bar) • Mass ~ 1530 MeV/c2 • Width ~ 15 MeV/c2 • Decays equally to n K+ and p Ko Recently updated nK+ pKo 10 experiments report evidence [Q+] 3 experiments report no observation (HERA-B, PHENIX, BES)

  7. Search Mode: • + →Ksop+  + - Check Modes: • f →K+K- • K*o→K+p - • L(1520)→p+K- • K*+→Ksop + f K+K- L(1520) p+K- Kso  p+p- K*o(892)  K+p- K*+(892) Kosp+

  8. Search Mode: • + →Ksop+  + - Check Modes: • f →K+K- • K*o→K+p - • L(1520)→p+K- • K*+→Ksop + Nothing at 1540 GeV Two triggers Minbias 23 × 106 events jet20: 14 × 106 events

  9. Search Mode: • co D*+p(bar) Do+ K- + Check Mode: • D1(2420) D*+ - Do+ K- + • D*2(2460) D*+ - Do+ K- + L ~ 240 pb-1 All tracks “good tracks” All vertices (² < 30) N(Do)~ 3 M events σ(Do) ~ 8 MeV/c² Pt() > 400 MeV/c 1.845 < M(Do) < 1.885 GeV/c² N(D*) ~0.5 M events, σ(D*)~ 1.2 MeV /c² Pt() > 500 MeV/c M(D*) - M(Do) range 143.6 - 147.2 GeV/c² N[D 1(2420), D*2(2460)] ~15k events Do D*+ D1(2420), D*2(2460)

  10. Search Mode: • co D*+p(bar) Do+ K- + Check Mode: • D1(2420) D*+ - Do+ K- + • D*2(2460) D*+ - Do+ K- + H1: Claims co(3099) M = 3099 ± 3 (stat.) ± 5 (syst.) MeV s = 12 ± 3 (stat.) MeV No PID TOF dE/dx CDF CDF CDF Phys.Lett.B588:17,2004

  11. Search Mode: • oc  D*+ p • oc  D+ p • -c  Do p • -c  Do p Plus charge congugate states • oc  D*-p • oc  D-p • +c  Do p • +c  Do p Do p Do p PID likelihood ratio: New: 20-Oct-2004

  12. Search Modes: •3/2-- [F3/2--] -- L- -p • 3/2o [F3/2o] -+ L - -p Check Mode: (1530) -+ L- -p NA49: arXiv:hep-ex/0310014

  13. Search Modes • Rs+ J/p+ l +l - Check Mode: • B± J/K ± l +l - Conventional wisdom (?) dictates that if pentaquarks exist and follow the standard rules of QCD, then there should exist pentaquarks like Qc and Qb Estimates have these as parity (P = +1) states with masses such that they are likely to be able to decay strongly. Recent work has suggested that there could exist pentaquarks that have which internal angular momenta that gives the pentaquark parity (P = -1) and makes them more likely to be strong-decay forbidden. B± Stewart, Wesling, Wise hep-ph/0402076

  14. Search Modes • Rs+ J/p+ l +l - Check Mode: • B± J/K ± l +l - Because Rs+ is only theoretical construct, search looks in broad mass range and with separate assumptions on force governing decay. Cutting at 2D decay length of 100 mm distinguishes between No Lxy cut Lxy > 100 mm immediate and long-lived Rs+ decay. Mass window of 5725 – 6380 MeV explored. No evidence for signal.

  15. Search Modes: • + →Ksop + - •co D*+p(bar) Do+ K- + • 3/2--/o [F] -- L - -p • Rs+ J/p+ l +l - Pentaquark Summary While CDF has done an admirable job of establishing all of their sensitivity-establishing signals, no candidate pentaquark signal observed. Failure to observe pentaquark candidates highlights need for theoretical guidance. Perhaps pentaquark creation suppressed at high Work continues.

  16. X(3872)  J/p+p- • First observed by Belle B+ K+ X(3872) decays • Signal confirmed by CDF, DØ and BaBar • Nature of X(3872) unknown • Theories include: • Another charmonium state • D D* molecular state • Since the X(3872) lies very close in mass to the (2S) charmonium state, and has a common decay mode (X  J/p+ p- ), we compare production and decay properties of these two states through this decay mode.

  17. Announced by BELLE in 2003  • Local interest • - 1994: E705 (fixed target at FNAL) • in p LiJ/ p+p- + anything • observed 58 ± 21 excess events • at 3.838 ± 0.013 GeV • [PRD 504258 (1994)] • possible interpretations • 1P1(1+ -), 3D2(2- -), 1F3(3+ -)cc or ccqq • - 1995: E672/E70652 ± 30 events BELLE E705 E672/E706

  18. X(3872) confirmed by CDF & DØ Belle:MX = 3872.0  0.6  0.5 MeV

  19. X(3872) –y(2S) comparison • Is the Xcharmonium, D – D* molecule, ccg hybrid, … ? • No significant differences between(2S)and Xhave been observed yet • From isolation and decay length comparisons, the production of X appears to have • the same mixture of prompt and long-lived fractions as the(2S) pT (J/  pp) > 15 GeV Decay Length < 0.01cm |y| <1 Cos(qp) < 0.4 Isolation = 1 Cos(qm) < 0.4

  20. X(3872): “Lifetime” Distribution • Proper Lifetime Since both decay strongly, any lifetime reflects the parent particle (c.f. B+ K+ J/p+ p- ).

  21. Heavy Flavor Results The above list are only analyses that have publicly accessible results. Other analyses are ongoing. Published/Submitted

  22. B Hadron Lifetimes: Expectations and Existing Data • Heavy Quark ExpansionTheory predicts lifetime ratios in rough agreement with data • Experimental and theoretical uncertainties are comparable • Tevatron the best source of Bsand Lb • Goal measure the ratios accurately

  23. Exclusive B Lifetimes; CDF results Lifetime Ratios(most systematic uncertainties 100 % correlated) • t (B+) / t (B0) = 1.080 ± 0.042 (tot.) t (Bs) / t (B0) = 0.890 ± 0.072 (tot.)

  24. Exclusive B Lifetimes; DØ results Lb L J/ Lifetime Ratios(most systematic uncertainties 100 % correlated)

  25. Run I Published/Submitted Summary - lifetimes • Current Status: • DØ measurement of t(B+)/t(Bo), novel technique, single measurement comparable to world average. • Results competitive with B-factories, expect 1% ratio precision (2 fb-1) • Tevatron t(Bs) results are predominantly from a CP-even mode, which may differ from the typical semi-leptonic states, which are equally CP even and odd.

  26. High Q2 Physics: The Final Stretch • In addition to ~ few GeV hadronic physics, Tevatron probes hardest scatters available to modern accelerators. • High Pt inclusive and dijet mass cross-sections are typical. • Restrict analyses presented to ones with b-quark final content. • bb dijet mass • Inclusive b-jet cross-section (h,f) cone collects nearly-collinear particles Resultant “jet” reflects kinematics of parent (“hard-scatter) parton. Basically jet  parton

  27. bb dijet mass • 2 jets |h | < 1.2 • Both tagged with 2VTX • Pt1 > 30 GeV • Pt2 > 10 GeV • B fraction determined by • Electron PtRel • 2VTX Mass • Very preliminary result

  28. Result: While only very preliminary, CDF’s inclusive b cross-section in broad agreement with shape from Leading Order Monte Carlo. b inclusive xsec • 150 pb-1 • 0.1 < |hjet| < 0.7 • 30 < Pt(jet) < 210 GeV • 2VTX tagged • |DR(h,f)| < 0.7 • Compare to Pythia • Shape only • Luminosity not included Similar DØ result imminent

  29. Summary • No pentaquark signal observed at the Tevatron • X(3872) confirmed and preliminary study of decay properties resemble (2S). • Many heavy-flavor spectroscopy results • Competitive with b factories • Certain signals (Lb, Bs, etc.) only available at Tevatron. • Many high Q2 results, including exclusive heavy-flavor states, available or pending.

  30. References • DØ b-spectroscopy, X(3872) • http://www-d0.fnal.gov/Run2Physics/WWW/results/B/b.htm • DØ high Q2 results • http://www-d0.fnal.gov/Run2Physics/WWW/results/QCD/qcd.htm • CDF b-spectroscopy, pentaquark, X(3872) • http://www-cdf.fnal.gov/physics/new/bottom/bottom.html • CDF high Q2 results • http://www-cdf.fnal.gov/physics/new/qcd/QCD.html • This conference: • Yesterday, parallel sessions A2 (Litvintsev), B1 (Gomez-Ceballos • & Zweber), B2 (D’Auria) and B3 (Bishai)

  31. www-d0.fnal.gov/~lucifer/PowerPoint/APSTopical2004.ppt

  32. Backup Slides

  33. Novel Method to Determine t(B+)/t(Bo) Use: Bd 89 ± 3% B+ 10 ± 3% Bs 1 ± 1% Bd 83 ± 3% B+ 15 ± 4% Bs 2 ± 1% Calculate: and plot as a function of decay length

  34. Was I right? Published June 2004, World Scientific Publishing Company [End note: Beginning towards the end of 2002 and becoming more solid during the summer of 2003, several groups have observed a new particle, called the Q+. Current thinking is that this particle consists of four quarks and an antiquark, specifically two ups, two downs and a strange antiquark (uudds). The data is fairly compelling and will probably stand the test of time. … Physicists, both experimental and theoretical, are trying to reconcile the theory and data. Stay tuned, as with the next edition of this book, I may need to rewrite this chapter. Science is always exciting!!!]

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