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B, λ B and Charm results from the Tevatron

B, λ B and Charm results from the Tevatron. Physics in Collision: Zeuthen, June 27 2003. Farrukh Azfar, Oxford University (CDF). Overview of this presentation :. Tevatron performance & Beauty Physics at the Tevatron 2) CDF and D0 detectors and triggers

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B, λ B and Charm results from the Tevatron

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  1. B,λBand Charm results fromthe Tevatron Physics in Collision: Zeuthen, June 27 2003 Farrukh Azfar, Oxford University (CDF)

  2. Overview of this presentation: • Tevatron performance & Beauty Physics at the Tevatron 2) CDF and D0 detectors and triggers • Data from various Triggers at CDF and D0 • Physics Results : Masses and Lifetimes of B hadrons Tests of Heavy Quark Expansion (HQE) 4) Physics Results: Charm : masses, search for CP violation (CPV) & Flavour Changing Neutral Current (FCNC) 5) Physics Prospects: CP violation, Bs mixing (xs=Dms/G) and Bs width difference (DGs) 6) Conclusion and Summary

  3. Tevatron pp collider upgrade & performance Run-I (1992-1996) -Accumulated Ldt=110 pb-1 Run-IIa -Goals are Ldt=2fb-1 (x20 Run-I) Run-II Tevatron Upgrades: Main Injector -New Injection stage for Tevatron -Higher proton intensity -Anti-proton transfer efficiency increased -Anti-proton recycler (work in progress) Performance Improvement: -Collision rate: 3.5 ms  396 ns -6x6 bunches 36x36 bunches -Center of Mass energy: 1.8 1.96 TeV/c2 -Peak luminosity : 2.4x1031 4.4 x1031cm2s-1 (Below target by x4, steadily improving)

  4. Data taking performance CDF & D0 CDF integratedluminosity: -Delivered 230pb-1 of which -175pb-1 to tape, of which -70 pb-1 has important systems on (eg. Silicon) B-physics analyses D0 efficiency: -50 pb-1B-physics analyses Physics Results in this talk are from ~70pb-1 @ CDF and ~50pb-1 @ D0

  5. Why Beauty at the Tevatron ? s(bb) at (4S) = 1nb (B-factories) s(bb) at Z0 = 7nb (LEP) s(bb) at pp (1.96TeV/c2)=150mb (Tevatron Experiments) More B @ Tevatron but inelastic s at tevatron is 103 x s(bb) -Must select b-data online, key: appropriate detector & triggers -Rewards: can produce all B-hadrons eg B, B0, Bs, Bc , b …etc (unlike B-factories) & higher s than at Z0 Signatures for B Selection & use at CDF & D0: -High PT leptons from b mnX or b enX (CDF & D0) -Di-leptons from B J/yX, J/y  m+m- (CDF & D0) -Utilize long B and charm lifetimeslarge impact parameter (IP) of daughter tracks (CDF, D0 in progress)

  6. New: Time of Flight (TOF): some hadron ID New: Silicon (SVT) online Si tracker: Select high IP tracks from b and c @ trigger level(First time at a hadron collider !) Improvements over Run-I -Silicon Detector : 3-D tracking, 5 layers: B vertex, track IP resolution, -Faster Drift Chamber : Momentum measurement -Greater muon coverage : Select b, c m The CDF & D0 Detectors in Run-II CDF Detector New : 2T Super conducting Magnet New: Silicon tracker (vertex, track IP resolution) New: Fiber tracker : Momentum New: Si Track Trigger (displaced vertices) (Coming soon) Improvements over Run-I -Calorimetry and faster readout -Upgraded muon system. D0 Detector D0 has a magnetic field, and is able to pursue a competitive B-physics program as well !

  7. Data Samples: The J/y m+m- at CDF and D0 (Run-II) 75K at D0, completely new capability ! (40 pb-1) 0.5M at CDF (70 pb-1) Two Fully Reconstructed B-hadron J/y states at CDF &D0 B J/y KS:CDF:220, D0:45 (Run-II) (D0 had none in Run-I) LB J/yL :CDF:53, D0:16 (Run-II)

  8. Data Samples: B and Charm Using the high Impact Parameter (IP) (Hadronic) trigger Select events by requiring : -2 tracks with IP>100 mm - track PT > 2GeV/c - sum 2-track PT > 5.5 GeV/c 0.5M Charm decays at CDF 10-20% come from B: Great Potential for B and Charm Physics, opens at least as many avenues as J/y trigger

  9. Data Samples: B(+)l+uD decays using “hybrid” trigger One lepton (PT>3 GeV/c) & one high IP (>120mm)track: -High IP track means we can go lower in lepton PT -Statistics much higher than Run-I (lower PT thresholds) (x4-5 increase in statistics) Used for: 1) High statistics lifetime and mixing analyses 2) calibration samples for tagging (B+ l+nD) Drawback: worse vertex resolution due to missed neutrino Some numbers: BglD0X (D0gKp):~10000 events, BglD+X (D+gKpp):~5,000 events also Bs decays (later)

  10. Physics Results: lifetime, mass, from fully reconstructed BJ/y X modes: Standard Technique : Data from J/ym+m- di-muon trigger: - Reconstruct vertex - Calculate decay proper time, mass & errors - Fitting for Mass:fit mass only - Fitting for Lifetime:Fit mass and lifetime distributions in single step Probability Density Function and normalization: An Example B+J/y K+ at CDF Technique applied to several decays : B+gJ/y K+, B0gJ/y K0* (K0* g Kp), Bsg J/yf (fgKK) & LbgJ/yL (Lgpp)

  11. J/ym+m-and f K+K-(using di-muon (J/y) trigger): 1) Run-I: we had ~60 at CDF. 2) Run-II: we have ~136 at D0 and CDF : World’s largest sample of fully reconstructed Bs decays remains at the Tevatron Physics Results: BsJ/y f, Lifetime and Mass: CDF: M(Bs) = 5365.5  1.29(stat)0.94 (sys) MeV/c2, D0: M(Bs) = 5360  5CDF:t(Bs) = 1.26  0.2 (stat) 0.02(sys) ps, D0 lifetime analysis in progress Fit has one lifetime (width) but this mode contains two lifetimes: CP even and CP odd Bs With higher statistics we can use angular variables & disentangle CP states & fit two lifetimes (widths) Why is the width difference interesting ? -Bs width difference DGs: predicted to be large ~10% -SM : DGs=A.xs (xs=Bs mixing Parameter) -If xs is large and DGs is small or vice-versa sign of new physics -SM CP violation in Bs J/yf ~3% if extra-SM CP violation phase =Sin2e then DG s,measured = DG s,SM.Cos2e (DGsand CPV are complementary)

  12. Physics Results:LB, lepton+displaced track and purely hadronic data samples (have shown J/y mode already) b cl  [pK] l Protons are easiest to separate using Time of Flight Particle ID in left plot using TOF and dE/dX Lifetime in hadronic, hadron+lepton modes require correction for IP cut bias & missing  Expect results this summer b cp [pK] p Note on LB A search for CP violation in Baryon decays is planned using LB pp

  13. HQE Predicted B Lifetime hierarchy : tBc << tXb0 ~ tLb < tBd ~ tBs < t B- < t Xb- Physics Results:Testing HQE: A summary of results: • CDF (70 pb-1):t(B+)=1.570.070.02 ps using (B+ J/yK+) • t(B0)=1.42 0.090.02 ps using (Bd J/yK*0) • t(B+)/t(Bd)= 1.11 0.09 (Run-II) • t(Bs)/t(Bd)= 0.89 0.15 (Run-II) • D0 (40 pb-1):t(B+)=1.76  0.24ps using (B+J/yK+) BELLE (PRL 88 171801 2002) using BdD(*)-(p+,r+), J/yKS,J/yK*0 and B+D0p+, J/yK+ t(B+)/t(Bd)= 1.091±0.023±0.014 BABAR : fully reconstructed decays Bd D(*)-(p+,r+,a1+), J/yKS,J/yK*0 and B+D0p+, J/yK+ t(B+)/t(Bd)= 1.082±0.026±0.012 BABAR : partially reconstructed decays(BD,D* l n) t(B+)/t(Bd)= 1.064 ±0.031 ±0.026

  14. Physics Results:Testing HQE: A summary of results: s(t(B+)/t(Bd)) surpasses theory: 1.067 0.027 (HQE) (@ both Tevatron and B-factories) s(t(Bs)/t(Bd)) doesn’t (yet): 0.998 0.015 (HQE) Tevatron: Projection: s(t(Bs)/t(Bd) ) and s(t(Bd)/t(Lb)) <1% in Run-II important test for HQE Current LB lifetime is below HQE prediction, with LB J/yL can have unambiguous determination These results also give us confidence that vertexing works very well this is a crucial ingredient for Bs mixing and CP violation studies (more later)

  15. Physics Results: Charm physics at CDF: Ds±-D± mass difference First Run-II publication from CDF-comparable with recent results 1) Data Selected from the hadronic trigger 2) BothDs±,D±decay to fp±with fK+K- 3) Kinematics of both decays ~identical 4) Simply measure difference Ds± - D± mass difference 2400 Ds and 1600 D in only 11.6 pb-1 of data m = 99.28 ± 0.43 ± 0.27MeV/c2 In agreement with old world average: 99.2 ± 0.5 MeV/c2 (PDG: CLEO2, E691) and with recent BaBar result: 98.4 ±0.1 (stat) ±0.3 (syst) Mev/c2

  16. Physics Results: Charm physics at CDF: Search for Flavour Changing Neutral Current decay D0m+m- SM predicts a branching ratio (BR) of O(~10-13) for D0m+m- Some R-parity violating SUSY models predict branching ratios upto O(~10-6) • Technique: • D0p+p- BR is well known ~ identical acceptance • to D0 m+m- • 2) Use D0*±D0p± to tag D0 in D0K-p+ (thus no K vs p ambiguity) • 3) See how many ps fake ms per PT • 5) Look for D0 m+m-in same sample • 6) Subtract D0p+p- faking D0m+m- • 0 events found in 2s search • window CDF Result: BR(D0m+m) < 2.4x10-6 better than most recent world average: ( PDG 90%CL: < 4.1 x 10-6 ) A similar analysis of the rare decay Bs m+m- establishes a 4s sensitivity to signal for branching ratios >3.3x10-6

  17. Physics Results: Charm physics at CDF: Search for CP violation (CPV) in Charm decays: 1) c and u quarks don’t couple to tbox diagram contributions are tiny 2) CPV in charm decays  due to interference in decay (direct CPV) 3) SM prediction O(0.1-1%) CP violation effects in Charm Decays How: Compare rate of Decay of D0, D0 to CP eigenstates f=K+K- and p+p- • Method Using data from Hadronic Trigger • -Collect D*±D0p± : sign of p tags flavour of D • -Search for D0 K+K-, D0 p+p-, D0 p+p- & D0 K+K- • Correct for tracking efficiency for + vs - p from D*±D0p± • -Count number of decays in each mode after corrections

  18. Physics Results: Charm physics at CDF: Search for CP violation in Charm decays: Cross-check: Measure Ratio of Branching Ratios @CDF G(D0 p+p-)/G(D0 K+p-)=9.38±0.18±0.10% G(D0 K+K-)/G(D0 K+p-)=3.686 ± 0.076 ±0.036% FOCUS: G(D0 p+p-)/G(D0 K+p-)=9.93±0.14±0.14% G(D0 K+K-)/G(D0 K+p-)=3.53±0.12±0.06% CDF accuracy is comparable and consistent withFOCUS (2003) and World average 2.88±0.15 (PDG) 93560 D*±D0p± withD0K+p- 3697 D*±D0p±,D0 p+p- …8320 D*±D0p±,D0 K+K- CLEO Result (2001) First attempt at measuring CPV at CDF in Run-II ACP(D0 (p+p-))= 0.0±2.2±0.8% ACP(D0 (K+K-))= 1.9 ±3.2±0.8% ACP(D0 (p+p-))=2.0±1.7±0.6% (PDG 0.5±1.6%) ACP(D0 (K+K-))=3.0±1.9±0.6%(PDG 2.1±2.6%)

  19. Mixing and CP violation (CPV) in B decays Key Issues: Tagging Flavour Correctly… ...& being able to tag at all Statistical power: eD2 N events count for eD2N pure events Opposite side tagging Same side tagging Concept:Look for B on opposite side of B of interest -Look for m,e -Look for p or K -Use weighted jet-charge Disadvantages: Opposite B not in acceptance (60%) or mixes (B0) Concept: Look for charged tracks around reconstructed B of interest, Higher e Look for m,e from B decay Look for p± (K±) from hadronization of B (Bs) Sharpen algorithms on B± decays (where b-flavour is known eg B±J/yK± ) CDF:D2working on using TOF to do Kaon tagging & first mixing analyses to quote a final number D0:D2= 3.1 % Jet Charge, D2 = 4.7 % Lepton

  20. Mixing and CPviolation (CPV) at Hadron colliders: Run-I, CDF were able to do2smeasurementof sin2b & competitive xd (Dmd/G) measurements: can do tagging in hadron collider environment Sin2b=0.79±0.39(stat)±0.16(sys) (CDF 1996) Sin2b=0.76 ±0.067(stat)±0.034(sys) (BaBar 2002) Sin2b=0.719±0.07(stat)±0.035(sys) (Belle 2002) CDF: In Run-II with 40-50 x more Bd J/yKS decays can get d(sin2b)~0.05: D0: Similar statistics Can’t be competitive with BaBar and BELLE Redo the measurement because: -It’s an important benchmark -Gives credence to other CPV measurements eg. in B h+h- & Bs J/yf

  21. Physics Prospects: Toward Bs mixing at CDF : fully reconstructed decays Decays we plan to use: B0s Ds, B0s Ds Proper time resolution: t = 45 fs  t  PT/PT First observation of mode BsDs+p-with(Ds+fp+, fK+K-) ! -Need to tag initial B flavour -projection awaits final eD2 Plan to increase statistics from: . More efficient online SVT (Silicon Tracker) utilizing any 4/5 Si layers . Dynamic pre-scaling of trigger at Level2 (hadronic trigger) (x2-4) . Reconstruct with more Ds decays eg: K*0K, +

  22. Aside: Physics Results: Ratio of branching ratiosof BsDs ±p ±toBdD ±p ± Interest in Bs Ds± p± is mostly due to Bs mixing but:we’ve also measured the ratio of branching ratios G(Bs Ds± p±)/G(Bd D±p±) Normalization mode is Bd D ±p ±, D±K±p+p- Kinematically ~Bs Ds ±p±, Ds ±fp ±, f K+K- Using: -numbers of Bs and Bd in our signals -efficiencies from Monte-Carlo -D ±, Ds ± BR are from PDG, obtain: Using fs/fd =0.273±0.034 from PDG obtain: …we’re beginning to fill in PDG section on the Bs

  23. Physics prospects:Back to Bs mixing at CDF: partially reconstructed decays Use new “hybrid” displaced track+single lepton trigger Decays included:Accounting for missed neutrino Bs  Dsl, Ds*l (Ds, K*0K, +) expect ~40K events in 2 fb-1 st is worse due to missed u (K factor) : t = 60 fs  t  K/K, K/K ~ 14% If one Bs lifetime is fit in any flavour specific mode: tfit = (tBsCP+2+tBsCP-2)/(tBsCP++tBsCP-) from which DGs can be determined as well

  24. - u W d u,c,t b b d u W - u W s u,c,t b s b u W Physics Prospects: CP violation in Bh+h- decays determining angleg (CDF), Method: Tree and penguin graphs for Bp+p- & BsK+K- Five observables, Tree > penguin in Bp+p- vice-versa in BsK+K- -CP Asymmetry in Bp+p- = Sin2(g+b) (without penguin) -CP Asymmetry in BsK+K- = Sin2g (without penguin) -Assume SU(3) symmetry: replace s-d Hadronic matrix element ratios : penguin/tree same for both modes Four unknowns: d=ratio of penguin/tree hadronic matrix elements q= phase of d g,b= weak phases Constrain Sin2b from B-factories, & CDF/D0 results and measure g Proposed by: R.Fleischer, PLB459 1999 306

  25. Physics Prospects: CP violation in Bh+h- decays determining angleg (CDF) Monte-Carlo plot below shows: Bdp+p-,Bs K+K-BsK±p±, & BdK±p± (From Monte-Carlo)-all pile up in the same region B h+h- from hadronic trigger Includes Bp+p-,BsK+K- BsK±p±,and BdK±p± Must disentangle contributions from each mode to signal To do this we (will) use: -dE/dx based K and p identification -Kinematical variable separation M vs a=(1-p1/p2)q1 -Width of signal -Frequency of oscillationin CP asymmetry

  26. Physics Prospects: CP violation in Bh+h-: angleg (CDF) dE/dx calibration using D*± D0p, D0 K±p ±(p from D* unambiguously distinguishes K, p from D0) Mpp vs a for each Bh+h- mode Sanity check: Measure Ratio of Branching Ratios CDF :G(Bd p+p-)/G(BdK+p-) = 0.26 ±0.11±0.055, PDG: Method works ! Confirmed by Sanity check against ratio of branching ratios Have first observation of Bs K+K- Its a CP Eigenstate: Can use this To measure DGs as well !! Yield for each mode: Bd p+p- 14817 Bd K±p± 3914 Bs K± p± 311 Bs K+K- 9017 First observation ! Back to projection of g measurement: Expected (2fb-1) accuracy: () =±10(stat) ±3(syst) (syst: SU(3) breaking)

  27. CDF & D0 are in the first phase (<200pb-1) of data taking expect to: • a) Test HQE especially with LB and Bs • b) Search for CPV and FCNC in Charm & B rare decays • c) Establish tagging and lifetime measurement techniques with new data • 2) Next phase (>200pb-1 &<500pb-1) will: • a) set limits on (or measure) Bs mixing • b) search for CPV in the neutral B system • 3) Final Phase (end Run-IIa) (>500pb-1 and <2fb-1) measure: • a) Bs width difference DGs & mixing parameter xs • c) CKM angle g • d) search for CPV in LB pp • e) ……and search for unexpectedly large CPV in BsJ/yf • Pursue in the first phases a program partially in parallel to and in the last phase complementary to the B-factories Conclusions:

  28. Backup Slides

  29. Aside: Physics Results: Ratio of branching ratiosof BsDsp toBdDp Interest in BsDsp is mostly due to Bs mixing but:we’ve also measured the ratio of branching ratios G(BsDsp)/G(BdDp) Normalization mode is Bd Dp, D Kp+p- Kinematically ~BsDsp, Ds fp, f K+K- Ratio of Bs to Bd signals is: Where e are determined from Monte-Carlo D, Ds BR are from PDG, obtain: Using fs/fd =0.273±0.034 from PDG obtain: …we’re beginning to fill in PDG section on the Bs

  30. Signal lifetime is modelled by : Complete likelihood function: Complete event probability density Background shape from side-bands Physics Results:Average B-hadron lifetime from partially reconstructed BJ/yX decays. This is a “sanity check” of our BJ/y sample: Obtain Average B hadron tB From all B J/y (+other stuff) decays: B is not fully reconstructed If Fully reconstructed B -ct= c.(time in B rest frame) -Lxy = 2-d decay length -MB = mass -PT = transverse momentum D0 Inclusive B Lifetime If Partially reconstructed B -Correct for missed daughters: F(PT) (from by Monte-Carlo) -tB is an estimate -it is the average lifetime of all hadrons decaying to J/y Results from D0 and CDF tB=1.5610.0240.074 ps D0 (40 pb-1) tB=1.5260.0340.035 ps CDF (18 pb-1) Both consistent with: PDG: tB= 1.564  0.014

  31. Jan 03 Mar 02 CDF Integrated Luminosity Data used for Today’s results Mar 02 – Jan 03 130 pb-1 (delivered) 100 pb-1 (to tape) B/Charm: ~ 70 pb-1 commissioning

  32. Physics Prospects: Bs width difference using Bs J/yf • One lifetime(width) has been fit in this mode • But contains two distinct lifetimes: CP+ & CP- Bs, significant lifetime (width) difference: • DGs=1/tB1-1/tB2 • 2) Extract DGs : fit two lifetimes, use single angle to separate CP+ and CP- Bs: (Transversity angle q) • SM prediction forDGs ~0.10Gs alsoDGs= A.xs (xs = Bs mixing parameter)ifDGsis smalland xs is large or vice-versaSign of new physics • CDF prediction for 2fb-1 d(DGs)~0.05 Two CP states: transversity Two CP states: lifetime Total function and normalization Current limit (LEP):s / s <0.31, from branching ratio of BsDs±(*)Ds(*) Note: SM CP violation in this mode: O(3%), if large new physics CP asymmetry = sin2e  DGs, measured= DGs,SM.Cos2e (complementary)

  33. Physics Results: lifetime, mass, from fully reconstructed B J/y X modes: Standard Technique : Data from J/ym+m- di-muon trigger: 1) Reconstruct vertex according to decay topology 2) Calculate decay proper time mass & errors 3) If fitting for mass:fit mass only 4) If fitting for lifetime:Fit mass and lifetime using bi-variate Probability density function (PDF) in likelihood Probability Density Function (pdf) 1) Signal Lifetime : 2) Signal Mass : An Example B+ ->J/y K+ at CDF 3) Signal for Mass only analyses: 4) Signal pdf in mass and lifetime: 5) Signal for lifetime analysis: Both the mass and lifetime distributions are fit in a single step. Technique is applied to : B+gJ/y K+, B0gJ/y K0* (K0* g Kp), Bsg J/yf (fgKK), LbgJ/yL (Lgpp) 6) Normalization : mass and lifetime

  34. B physics prospects(with 2fb-1) Both competitive and complementary to B -factories • Bs mixing: Bs →Dsπ(Ds3π)(xsup to 60, with xd meas. one side of U.T.) • Angle : B0→ J/ψ Ks(refine Run1 meas. up to (sen2)  0.05) • CP violation, angleγ: B0→ ππ(πK), Bs→ KK(Kπ) • Angle s and s/ s : Bs→ J/ψ(probe for New Physics) • Precise Lifetimes, Masses, BRfor all B-hadrons: Bs, Bc, Λb … (CDF observed: Bc → J/ψ e(). Now hadronic channels Bc → Bs X can be explored) • HF cross sections (beauty and charm) • Stringent tests of SM … or evidence for new physics !!

  35. 1 B 1   » ) + ( sin (2 ) e D N S 2 ms/md a Sin(2) in B0J/y Ks g b N(B0)(t) - N(B0)(t) ACP(t) = =Dsin(2b)sin(Dmd t) N(B0)(t) + N(B0)(t) In Run1 measured: B0  J/ Ks ; J/   sin(2b)=0.79±0.39±0.16 (400 events) sin(2b)=0.91±0.32±0.18 (+60 B0   (2S) Ks) With 2fb-1 can refine this measurement Although: no way to compete with B-Factories ! N(J/ Ks) from scaling Run I data: • x 20 luminosity 8,000 • x 1.25 tracks at L1 trigger 10,000 • x 2 muon acceptance 20,000 • Trigger on J/  e+e+ 10,000 Stat. Error: Expect: s(sin2b)  0.05 Systematic ~ 0.5xStatistical (scales with control sample statistics) Combined eD2: from 6.3% to 9.1%(Kaon b-tag) Same S/B = 1

  36. Tevatron Performance 3.8 x 1031 • Tevatron operations • Startup slow, but progress steady ! • Now:L ~3.5 x 1031 cm-2s-1 • integrating ~ 6. pb-1/week • … still factor 2-3 below planned values • additional improvements (~10-20%) expected from Jan. 3weeks shutdown Initial Luminosity July ‘01 Now • CDF operations • Commissioning: Summer 2001 • Physics data since February 2002 • Running with >90% Silicon integrated • since July 2002 On-tape Luminosity 110 pb -1 • Luminosity (on-tape): • ~20pb-1until June (analyses in this talk) • Additional 90pb-1 July – December • Reach 300- 400 pb-1 by October 2003 July ‘02 Feb ‘02

  37. Quadrant of CDF II Tracker TOF:100ps resolution, 2 sigma K/ separation for tracks below 1.6 GeV/c (significant improvement of Bs flavor tag effectiveness) TIME OF FLIGHT COT: large radius (1.4 m) Drift C. • 96 layers, 100ns drift time • Precise PT above 400 MeV/c • Precise 3D tracking in ||<1 (1/PT) ~ 0.1%GeV –1; (hit)~150m • dE/dx info provides 1 sigma K/ separation above 2 GeV • SVX-II + ISL: 6 (7) layers of double-side silicon (3cm < R < 30cm) • Standalone 3D tracking up to ||= 2 • Very good I.P. resolution: ~30m (~20 m with Layer00) LAYER 00: 1 layer of radiation-hard silicon at very small radius (1.5 cm) (achievable: 45 fs proper time resolution inBs Dsp )

  38. CDF II Trigger System 3 levels: 5 MHz (pp rate) 50 Hz (disk/tape storage rate) almost no dead time (< 10%) • XFT: “EXtremely Fast Tracker” • 2D COT track reconstruction at Level 1 • PT res. DpT/p2T = 2% (GeV-1) • azimuthal angle res. Df = 8 mrad • SVT: “Silicon Vertex Tracker” • precise 2D Silicon+XFT tracking at Level 2 • impact parameter res. d = 35 m • Offline accuracy !! CAL MUON CES COT SVX XFT XCES Matched to L1 ele. and muons XTRP enhanced J/ samples L1 CAL L1 TRACK L1 MUON GLOBAL L1 SVT L2 CAL CDF II can trigger on secondary vertices !! Select large B,D samples !! GLOBAL LEVEL 2 TSI/CLK

  39. COT track ( 2 parameters) 5 SVX coordinates beam spot d Impact Parameter (transverse projection) SVT: Triggering on impact parameters ~150 VME boards • Combines COT tracks (from XFT) with Silicon Hits (via pattern • matching) • Fits track parameters in the transverse plane (d, , PT)with offline res. • All this in ~15ms ! • Allows triggering on displaced impact parameters/vertices • CDF becomes a beauty/charm factory

  40. B triggers: conventional Needspecialized triggers (bb) /(pp)  10-3 CDF Run1, lepton-based triggers: • Di-leptons (, PT 2 GeV/c): B  J/ X, J/   • Single high PT lepton ( 8 GeV/c): B  l  D X Suffer of low BR and not fully rec. final state Nevertheless, many important measurements by CDF 1: B0d mixing, sin(2), B lifetimes, Bc observation, … • Now enhanced, thanks to XFT (precise tracking at L1) : • Reduced (21.5 GeV/c) and more effective PT thresholds • Increased muon and electron coverage • Also J/  ee

  41. XFT performance Efficiency curve: XFT threshold at PT=1.5 GeV/c  = 96.1 ± 0.1 % (L1 trigger) XFT: L1 trigger on tracks better than design resolution pT/p2T = 1.65% (GeV-1)  = 5.1 mrad Offline track XFT track 11 pb-1 53.000 J/  

  42. SVT performance • I.P. resolution as planned • d = 48 m = 35m  33 m intrinsic D0  Kp used as online monitor of the hadronic SVT triggers transverse beam size • Efficiency S/B  1 90% soon 80%

  43. TOF performance • TOF resolution (110ps) within 10% of design value Background reduction in KK: Low PT (< 1.5 GeV/c) track pairs before and after a cut on TOF kaon probability x20 bkg reduction, 80% signal efficiency with TOF PID S/N = 1/2.5 S/N = 1/40

  44. CDF J/y cross section 0<pt<0.25 GeV 5.0<pt<5.5 GeV 10.0<pt<12.0 GeV s(ppgJ/y; pT>0; |h|<0.6) =240  1 (stat) 35/28(syst) nb

  45. D0 K D0 KK D0  5670180 2020110 56320490 K mass KK mass  mass Lots of charm from hadronic triggers: With ~10 pb-1 of “hadronic trigger” data: Relative Br. Fractions of Cabibbo suppressed D0 decays : Already competitive with CLEO2 results (10fb-1 @ (4S)) !!!!! (DKK)/(DK) = 11.17  0.48(stat)  0.98 (syst) % (D )/(DK) = 3.37  0.20(stat)  0.16(syst) % O(107) fully reconstructed decays in 2fb-1 •  Foresee a quite interesting charm physics program: • D cross sections, • CP asymmetries and Mixing in D sector, Rare decays, …

  46. Data Samples: B and Charm from the hadronic trigger 0.5M Charm decays at CDF 10-20% come from B: Great Potential for B and Charm Physics, opens at least as many avenues as J/y trigger Some charm is prompt D from direct charm: Points back to beam spot ..Some charm is from B D from B has a impact Parameter wrt beam spot An example of B reconstructed Using data from this trigger: ..to separate prompt Ds from Ds coming from B Prompt Charm D0K86.5  0.4 % (stat) D*D087.6  1.1 % (stat) DK89.1  0.4 % (stat) Ds72.4  3.4 % (stat) We have B and tons of Charm as well !

  47. B0s mixing: expectations with 2fb-1 xs = ms(B0s) Bs Ds, Ds  Ds  , K*K,  • Signal: 20K (fp only) - 75K (all) events • with SVT hadronic trigger • BR (Ds ) = 0.3 % ; BR (Ds   ) = 0.8 % • Resolution: • (c)= 45 fs (with Layer00) • eD2 = 11.3% (with TOF) • S/B: 0.5-2 (based on CDF I data) S.M. allowed range: 20. < Xs < 35. 5s sensitivity up to: Xs = 63 (S/B = 2/1) Xs = 53 (S/B = 1/2) Can do a precise measurement … or evidence for new physics !

  48. Signal lifetime is modelled by : Complete likelihood function: Complete event probability density Background shape from side-bands Physics Results:Average B-hadron lifetime from partially reconstructed BJ/yX decays. This is a “sanity check” of our B J/y sample: Obtain Average B hadron tB From all B J/y (+other stuff) decays: B is not fully reconstructed D0 Inclusive B Lifetime Partially reconstructed B -Correct for missed daughters: F(PT) (from by Monte-Carlo) -tB is an estimate -it is the average lifetime of all hadrons decaying to J/y Results from D0 and CDF tB=1.5610.0240.074 ps D0 (40 pb-1) tB=1.5260.0340.035 ps CDF (18 pb-1) Both consistent with: PDG: tB= 1.564  0.014

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