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CDF hot topics

CDF hot topics. Sandro De Cecco FNAL & INFN Roma 1. Outline. Tevatron performances. CDF detector and B physics triggers . Recent and new results: B s mixing b-hadrons Lifetimes & DG s / G s L b modes Charmless B d,s decays Rare decays. Summary and perspectives.

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CDF hot topics

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  1. CDF hot topics Sandro De Cecco FNAL & INFN Roma 1 Sandro De Cecco - FNAL & INFN Roma

  2. Outline • Tevatron performances • CDF detector and B physics triggers • Recent and new results: • Bs mixing • b-hadrons Lifetimes &DGs/Gs • Lb modes • Charmless Bd,s decays • Rare decays • Summary and perspectives Sandro De Cecco - FNAL & INFN Roma

  3. Tevatron performances • CDF II has collected so far ~ 0.8 fb-1 out of >1 fb-1 delivered by Tevatron. • Record peak luminosity is ~1.3∙1032cm-2s-1 • Around 600 pb-1are availablefor B physics (good tracking detector conditions) • Current analysesuse 180 - 350 pb-1 of integrated luminosity Right on the track of stretched TeV plans 1 fb-1! Sandro De Cecco - FNAL & INFN Roma

  4. The CDF II detector CDF Tracking System • Lepton ID • Particle ID • Muons:CMU, CMP, CMX (||<1.1) • dE/dX in COT • Electrons: CEM (EM calorimeter) • CPR (pre-shower detector) • Time Of Flight detector Sandro De Cecco - FNAL & INFN Roma

  5. Lxy ~ 1 mm B decay Primary Vertex Secondary Vertex Impact Parameter( ~100mm) B Physics at pp collider • All B species produced: • Bu,Bd,Bs,Bc,b, b… • With production fractions: • fu : fd : fs : fL≈ 4 : 4 : 1 : 1 • Acceptance for other B is 20-40% BUT:(bb) << (pp) (~65 mb)B have to be selected with specificTriggers the Secondary Vertex Trigger SVT Example: • Online (L2) selection of displaced tracks • based on Silicon detector hits.  see talk by Mauro Dell’Orso • b production is so large (~300 Hz @ 1032 cm-2 Hz) that we could not even cope with writing it all to tape!  trigger quasi-exclusively on specific decay modes Sandro De Cecco - FNAL & INFN Roma

  6. B physics triggers at CDF II Conventional at colliders (Run I) With SVT trigger 2-Displaced tracks PT(trk) > 2 GeV 120 m < I.P.(trk) < 1mm SpT> 5.5 GeV fully hadronic modes 1-Displaced track + lepton (e, ) 120 m < I.P.(trk) < 1mm PT(lepton) > 4 GeV Semileptonic modes Di-Muon (J/) Pt() > 1.5 GeV J/ modes down to low Pt(J/)~0 (Run II) + Sandro De Cecco - FNAL & INFN Roma

  7. Mixing Sandro De Cecco - FNAL & INFN Roma

  8. Bs Mixing but: |Vts|>>|Vtd| Dms>>Dmd Measuring Dms/Dmddetermines |Vts|/|Vtd| Lattice calculation error O(5%) Fit with all constraints (winter 05): ρ= 0.190 ± 0.044 η = 0.349 ± 0.024 WA experimental limit: Dms > 14.5 ps-1 (95%CL) (LEP+SLD+CDF 1) Sandro De Cecco - FNAL & INFN Roma

  9. SM CKM-fit prediction for Dms SM New Physics models can allow high Dms (with all constraints) (Δms not used) compatibility plot Dms = 18.9 ± 1.6ps-1 [15.7, 23.0] @ 95% CL Δms = 20.5 ± 3.2ps-1 [14.4, 27.1] @ 95% CL If Dms > 30 ps-1 New Physics @ 3s Sandro De Cecco - FNAL & INFN Roma

  10. Analysis Strategy • Bs signal reconstruction • Flavour specific states • Bs decay time • proper time reconstruction • Lifetime measurement • Initial flavour of the Bs • Flavour tagging techniques • calibrate on Bd mixing B0A-scan •  B0 Mixing • perform a “Blind AMPLITUDE SCAN”: A Dmd = 0.5ps-1↔ A =1 Sandro De Cecco - FNAL & INFN Roma

  11. n p D B D B s s P.V. P.V. m,e s s Two different Bs signatures: Fully reconstructed HADRONIC modes: • Good proper time resolution • High Bs mass resolution • Selected by Two Track Trigger (SVT) SEMILEPTONIC modes: • Missing momentum carried by the n • Diluted proper time resolution • Selected by dedicated trigger (l+SVT): Sandro De Cecco - FNAL & INFN Roma

  12. Flavour tagging Same Side Opposite Side Used for today results Jet Charge: the sum of charges of the b-Jet tracks correlated to the b-flavour Soft Lepton (e,m) due to bℓnX ℓcharge correlated to b-flavour NOT yet used Same Side Kaon: for B0s is likely to have close in DR a K+. High eD2isexpected Muon Tag Calibrate the OS taggers on B0 mixing Sandro De Cecco - FNAL & INFN Roma

  13. World Average + CDF Run II Sensitivity: 18.2 18.6 ps-1 Limit: 14.5 ps-1 Bs Amplitude Scan results Semileptonic • Sensitivity:8.4 ps-1 • Limit:Dms >7.9 ps-1@ 95% CL Semileptonic Hadronic • Sensitivity:0.4 ps-1 • Limit:Dms >0 ps-1@ 95% CL Hadronic CDF winter ’05 Combined • Sensitivity: 8.4 ps-1 • Limit: Dms > 7.9 ps-1@ 95% CL  see talk by Marco Rescigno Sandro De Cecco - FNAL & INFN Roma

  14. Near future for Dms • With the SAME data: • Add new tagging algorithms Same Side Kaon Tag • Add more channels • Add signals from other triggers • Improve decay time resolution with PV event by event • With NEW data: • Increased Luminosity (0.8fb-1 on tape!) • Use new trigger strategies • 2 SVT Tracks + tagging muon at trigger level (already in place since summer 2004) x4 statistics +20% better ct res. • Hadronic analysis will begin to lead the sensitivity • Start to “eat” interesting Dms range (expect comb. sens. ~ 15ps-1) Sandro De Cecco - FNAL & INFN Roma

  15. NEW: additional semileptonic B decays • From the same data (360 pb-1) used • in mixing analysis: • Use SVT trigger(2 displaced and 2 GeV tracks) • Select e and moffline • Allow lower LEPTON PT (42GeV) • Increase the overall acceptance • of more than X 3 At low Lepton PT, expect more backgrounds from BDDX decays Sandro De Cecco - FNAL & INFN Roma

  16.  more semileptonicBsforDmsanalysis 2 displaced track trigger 4GeV-lepton + 1 displaced track trigger + • Additional new sample overlap with the one already used ~ 20% • Effective ~ X 3 more semileptonic Bs yield to be used for MIXING • Expect significant sensitivity increase in semileptonic Dms search Sandro De Cecco - FNAL & INFN Roma

  17. b-hadron lifetimes and DGs/Gs Sandro De Cecco - FNAL & INFN Roma

  18. 260 pb-1 13,300 Signal events Lifetimes in semileptonic B decays http://www-cdf.fnal.gov/physics/new/bottom/050224.blessed-bsemi-life/ • Largest statistics B sample • More complicated background (B+) = 1.653±0.029±0.032 ps, (B0) = 1.473±0.036±0.054 ps (B+)/(B0) = 1.123±0.040±0.040 • Full statistics sample still under study. • Statistical uncertainty expected: @ ~400 pb-1 Sandro De Cecco - FNAL & INFN Roma

  19. Lifetimes in fully reconstructed modes • Test for our ability to understand SVT trigger biases • Very clean samples • Prerequisite for mixing fits CDF ’05 preliminary result (B+) = 1.661±0.027±0.013 ps (B0) = 1.511±0.023±0.013 ps (Bs) = 1.598±0.097±0.017 ps KK Sandro De Cecco - FNAL & INFN Roma

  20. BsJ/y f and DGs / Gs • BS J/y fm+m- K+K- • BVV decays: Heavy and Light state decay with distinct angular distributions and different lifetimes. • Result (260 pb-1) • 1/4 heavy - 3/4 light state • Lifetime - theavy ~ 2 x tlight • Lifetime difference measures “same” CKM element as Dm (oscillation frequency) • Exciting!! Need more data • ~ 5 % sensitivity by 2009 • Dms = 10 ps-1 DGS / GS= 7% • Test still possible CP violation effect in Bs mixing Sandro De Cecco - FNAL & INFN Roma

  21. b-Barions Sandro De Cecco - FNAL & INFN Roma

  22. Lb modes • Lifetimes are an important experimental reference: • Overlap with B factories  understanding of detector/trigger/analysisbiases • Further test on species not produced at B factories: Lb Lc m X Theo. Exp. C. Tarantino, hep-ph/0310241 Oct 2003 Lb Branching ratios: Lb Lc p NEW: http://www-cdf.fnal.gov/physics/new/bottom/050407.blessed-lbbr/ Sandro De Cecco - FNAL & INFN Roma

  23. b Updated knowledge • Colors: • PDG2004 • CDF contribution beyond current PDG2004 Mass m = 5619.9  1.7 MeV/c2 Lb mass (4.1  2.0) x 10-3 Lc l u (5.5  1.8) % pK + pp < 2.2 x 10-5 Lc+p- p- p+seen Lc(2593) +l u seen Lc(2625)+l u seen Sc++p-l u seen Sc0p+l u seen Sandro De Cecco - FNAL & INFN Roma

  24. CP violation and charmless B decays Sandro De Cecco - FNAL & INFN Roma

  25. Charmless Bhh’ • Difficult competition with B factories for t-dependent tagged measurements • Interesting B physics measurement of Bs BR and ACP(B0Kp) • Signals overlap within mass resolution • Kinematic and dE/dX to disentangle components in a combined fit: Future:measure Bs lifetime in the CP even mode KK  extract DGs/Gs  see talk by Simone Donati Sandro De Cecco - FNAL & INFN Roma

  26. Charmless BVV decays  see talk by Simone Donati • Measured BR( Bsff) with 8 events (180 pb-1) • Update with 360 pb-1 • Will go soon for Polarization Amplitude analysis • Expected significance similar to B-factories Future:measure DGs/Gs in Bsff penguin mode Bd→fK* Bs→ff Bs→J/yf ~225 events ~125 events ~44 events TTT data overlap with 2m trigger: ~20% Sandro De Cecco - FNAL & INFN Roma

  27. Search for Bs,d mm  see talk by Sinead Farrington SM: BR(Bs) < 3.8∙10-9 Sensitive to new physics Ex.: NEW Results (360 pb-1): BR(Bs  mm) < 1.6×10-7 @ 90% CL < 2.1×10-7 @ 95% CL BR(Bd  mm) < 3.9×10-8 @ 90% CL < 5.1×10-8 @ 95% CL These are currently world best limits Sandro De Cecco - FNAL & INFN Roma

  28. … and also at BEAUTY 05: • Other VERY INTERESTING results from TEVATRON Heavy Flavour physics on: • Bc meson at CDF and D0 • X(3872) at CDF and D0  see talk by William Wester  see talk by Ulrich Kerzel Sandro De Cecco - FNAL & INFN Roma

  29. Conclusions • CDF performed the first Bs mixing analysis in run II • We foresee a substantial update with new samples, new data collected and improved tagging power for winter 2006 • Working to have world class measurements on b-hadron lifetimes and lifetime difference DGs/Gs • Perform complementary studies in the field of charmless B decays: Bd,shh, Bd,sVV, help digging the penguin sector • Huge CDF legacy of knowledge in Beauty to next generation B physics experiments. Sandro De Cecco - FNAL & INFN Roma

  30. Backup slides Sandro De Cecco - FNAL & INFN Roma

  31. COT track ( 2 parameters) 5 SVX coordinates Lxy ~ 1 mm B decay Primary Vertex Secondary Vertex Impact Parameter( ~100mm) beam spot d Impact Parameter (transverse projection) SVT: the hadronic B trigger • Online Impact parameter • Available at Level 2 trigger (20µs latency) • convolution of transverse size of the beam spot with the impact parameter resolution of the SVT: s≈47 mm ≈ 35mm + 30 mm SVT resolution Beam spot size Impact Parameter distribution Offline s ~ 45mm Sandro De Cecco - FNAL & INFN Roma

  32. Dms : systematic Uncertainties Semileptonic Hadronic • Dilution scale factors and templates • systematic limited from control sample • statistics • Physics background at low Dms • Prompt background at high Dms **Systematic errors are negligible with respect to statistical in both cases** Sandro De Cecco - FNAL & INFN Roma

  33. Heavy Flavour Production bb from HbX in 37 pb-1 of data! PRD 71, 032001 (2005) with first 6.5 pb-1 ! cc PRL 91, 241804 (2003) Sandro De Cecco - FNAL & INFN Roma

  34. Excited Heavy Flavor states • B**(L=1)  B • B J/K and D modes • Important to understand impact for Same Side Kaon tagging mixing Sandro De Cecco - FNAL & INFN Roma

  35. Welcome back to Bc http://www-cdf.fnal.gov/physics/new/bottom/050330.blessed-bc-jpsimu/ • Mode that gave the first evidence of the Bc (CDF Run I) • Large yield, no clean resonance though! 106 events 46.07.3 events • First signal of fully reconstructed Bc • Direct mass measurement! Sandro De Cecco - FNAL & INFN Roma Hep-ex/0505076

  36. Lifetimes: J/ modes http://www-cdf.fnal.gov/physics/new/bottom/040428.blessed-lft2/ • This was the starting point: • Clean unbiased sample • Precision measurement • Reference for biased (e.g. displaced track) triggers • Test for the understanding of: • Detector • Analysis technique • Sample composition Sandro De Cecco - FNAL & INFN Roma

  37. Decay time actually measure transverse quantities: Lxy , PT(B) Un-binned likelihood fit Used: and Lifetime in the hadronic Bs modes Combinatorial background ct template from high mass sideband Sandro De Cecco - FNAL & INFN Roma

  38. Hadronic B-lifetimes results CDF ± (stat) ± (syst) Systematic summary t(B+) = 1.66 ± 0.03 ± 0.01 ps t(B0) = 1.51 ± 0.02 ± 0.01 ps t(Bs) = 1.60 ± 0.10 ± 0.02 ps t(B+)/t(B0) = 1.10 ± 0.02 ± 0.01 t(Bs)/t(B0) = 1.06 ± 0.07 ± 0.01 World Average lifetimes (exp.): Theory prediction (see Cecilia Tarantino CKM05): t(B+) = 1.653 ± 0.014 ps t(B0) = 1.534 ± 0.013 ps t(Bs) = 1.469 ± 0.059 ps t(B+)/t(B0) = 1.06 ± 0.02 t(Bs)/t(B0) = 1.00 ± 0.01 Sandro De Cecco - FNAL & INFN Roma

  39. Lifetime in the semileptonic Bs modes ct = 455.9  11.9 mm ct = 413.8  20.1 mm ct = 422.6  25.7 mm Combined ℓ-Ds lifetime result:445.0  9.5 mm(W.A.: 438  17 mm) statistical err .only,NOT for Averages(DØ ’05: 426  13  17 mm) Real Ds backgrounds:prompt and physics Sandro De Cecco - FNAL & INFN Roma

  40. HQET: baryon lifetimes and B moments B lifetimes  Vcb Dominant uncertainty comes from HQET extraction! CDF can probe HQET and constrain it! http://www-cdf.fnal.gov/physics/new/bottom/030710.blessed-lambdab-lifetime/ blifetime C. Tarantino, hep-ph/0310241 Oct 2003 LO NLO LO NLO LO NLO Sandro De Cecco - FNAL & INFN Roma

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