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CDF Status and Prospects

CDF Status and Prospects. Stephen Miller University of Michigan 5 th International Conference on Hyperons, Charm and Beauty Hadrons June 28, 2002. CDF Run 2 Physics Program. Broad range of physics topics includes Top - Mass, Cross section, Single top->Vtb

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CDF Status and Prospects

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  1. CDF Status and Prospects Stephen Miller University of Michigan 5th International Conference on Hyperons, Charm and Beauty Hadrons June 28, 2002

  2. CDF Run 2 Physics Program • Broad range of physics topics includes Top - Mass, Cross section, Single top->Vtb Electroweak - W mass, Di-boson production QCD - High Et jets, photons, Di-jets(Mjj)-> Compositeness Charm - BR’s, Masses, Mixing Bottom - Rare decays, CKM constraints, Lifetimes, Mixing Higgs – Discovery/Exclusion Exotics - Susy, Large Extra dimensions, Z’ • Improve Run 1 measurements (110 pb-1) Expect 2 fb-1 for Run 2a Upgraded detector New capabilities

  3. CDF B Physics Goals • Measurement of CP Violation • B0→J/ψKs sin(2β) • B0→ππ sin(2α) • Bs →DsK sin(2γ) • Bs mixing measurement • Δms |Vtd|/|Vts| • Radiative B decays • B→K*γ, Bs →φγ, Λb →Λγ • Rare B decays • B0→µµ • Lifetimes, masses, BR’s • Bs , Bc , Λb (unique to Tevatron) • b production

  4. Ingredients for a B Measurement • e.g. Δmsfrom Bs→Dsπ • N depends on Luminosity Trigger cross section Reconstruction efficiency • S+B/S Reconstructed mass resolution • εD2 Flavor tagging Tagging efficiency ε Dilution D = 1-2w (w is mistag rate) Particle id • σt proper time resolution vertex resolution σLxy momentum resolution σPt (negligible) • limiting factor for Bs→Dslν mode

  5. Tevatron Upgrade • Upgrade for higher Luminosity • Tevatron Run I • 6x6 bunches with 3.5µs bunch spacing • Tevatron Run II • 36x36 bunches with 396ns spacing • Further upgrade to 132ns • (fewer interactions per crossing) • Main Ring replaced by Main Injector • Recycler • pbar source upgrade

  6. CDF Detector Upgrade Components from Run 1 Central and extension muon system Central & wall calorimeters Solenoid New for Run 2 Silicon tracker (more coverage, z measurements ) Central tracker (shorter drift time, improved stereo) Time of flight (All New!) End plug calorimeter (complete replacement) Central muon detector (Gaps filled in) Forward muon detectors (1 < |η| < 2) Luminosity Monitor Front end electronics (Run 1 bunch spacing 3.5µs, Run 2 spacing 396/132ns) Trigger (Higher rates, tracking at L1, svt tracks at L2) Software (Fortran → C++/Java)

  7. Silicon Layer 00 1 r-phi layer 1.4 cm from beamline Fully integrated with DAQ Improves impact parameter resolution SVXII 87 cm length (covers luminous region) 5 r-phi layers 3 r-z, 2 r-1.2° stereo Used for SVT trigger Intermediate Silicon Layer (ISL) r-phi and r-1.2° stereo all layers 1 layer |η| <1, 2 layers | η| <2 Gives tracks at higher eta Cooling problems have limited use but is being fixed

  8. Central Tracker • COT • 8 superlayers (4 axial, 4 2° stereo) • 12 measurements/superlayer, 30K channels • Smaller cell size than Run 1 tracker • needed for 132ns beam crossing period • Readout with Multi-hit TDCs • dE/dx encoded in pulse width • Hit resolution ~ 175µm COT working very well

  9. Tracking Performance COT: 99.7% single track efficiency COT+SVXII tracks: Preliminary resolutions: σd0 ≈ 23µm σLxy ≈ 60µm includes beam spot resolution of ≈ 35µm Still can improve alignments Numbers don’t include L00 Calibration of E-loss and B field Use J/ψ mass for calibration Cross checked with other particles Energy loss correction depends on material 0.56 g/cm2 layer added to detector description B field scaled by 0.13% dEdx measurement from COT hits Eloss+Bfield Improved Eloss E-loss default No E-loss

  10. Time of Flight • Detector • 216 scintillator bars • 2.8 m length • 4x4 cm^2 cross section • Coverage to |η| < 1 • Performance Goal of 100 ps time resolution gives 2 σ K/π separation for p<1.6 GeV/c 2 σ K/p separation for p<2.7 GeV/c 2 σπ/p separation for p<3.2 GeV/c Preliminary Calibration σ110 ps

  11. Time of Flight (cont) φ→KK reconstruction Using generic sample of tracks

  12. Calorimeter • Detector • Scint+Pb/Fe Towers with EM/Hadronic sections • Covers 15° in phi, 0.11 in η • 2-d strip/wire chamber at EM shower max • In Central region • Crucial for low energy electrons in trigger and analysis • Performance • Fully commissioned • Used for trigger and analysis • Energy scale calibrated to ~1%

  13. Muon Detectors • Central & Extension Muon Detectors • System commissioned and aligned • 95% live • Triggering on muon track stubs • Forward Muon Detectors (New) • System commissioned • 98% live • Alignment underway • Will be added to trigger

  14. 45 kHz 300-500 Hz 50 Hz ~20MB/s DAQ and Trigger • L1 Trigger • Calorimeter towers (Em and Hadronic Et) • SumEt, Missing Et • Muons • Tracks • Pt> 1.5 GeV. Matching for e, µ selection • L2 Trigger • Calorimeter clusters (plus isolation) • Track matched to Shower Max (electron id) • SVT tracks -> displaced tracks select b, charm • Processors calculate Lxy, (transverse) mass • L3 Trigger • Farm of 240 dual processor PC’s • All data available for making decision • Uses full reconstruction (offline code)

  15. Physics Goals and the Trigger B and Charm Physics • SVT tracks: Hadronic Bs, B→ππ, Charm • Displaced impact parameter, 2-D vertex, Lxy cut • Lepton + SVT: Semileptonic B, Radiative B • Dileptons: B→J/ψX • QCD • Jets • Diffractive triggers • Top • High Et lepton: W→lν • All Hadronic: ttbar→ 6 jets • Higgs • High Et lepton: HW production • B-tagging (d0 cut) for H→bbar • H→ττ • Exotics • High Et photons • Missing Et • Tau’s (cluster+ isolated track) • B-tagging

  16. Silicon Vertex Trigger (SVT) • Silicon based tracking at L2 • New capability at hadron collider • SVX readout on L1A • SVX chip digitizes and stores every 132 ns • Fast parallel readout over optical fiber • Track roads seeded by L1 XFT tracks • Lookup tables match to pattern of hits • Finds tracks with pt > 2 GeV • Currently match to 4 layers • Will change pattern to 4/5 • Track fit gives d0, curvature, phi0, χ2 • σd0≈35µm, σc≈6x10-6 cm-1σphi0≈1mrad • Correction required for beam offset • Beam spot measurement fed back to Tevatron to control beam position • Information available but not yet used

  17. PT Lxy secondary vertex R Beam spot Hadronic B Trigger • Physics goals • B→ππ, Bs →KK : CKM angle γ • Bs →Dsπ, Dsπππ : Bs mixing • Ds→φπ,K*K, KsK • Charm BR’s, masses • Selection • L1: 2 opposite charge tracks, Pt > 2GeV, Δφ cut, • dominates L1A bandwidth • L2: 2 svt tracks d0 > 100µm, Lxy cut • Yield for B events lower than expected • Will improve with SVX fixes and more efficient track patterns in SVT

  18. Lepton + SVT Track Trigger Physics goals Semileptonic B decays B cross section Fragmentation fraction Life time, B+/B0 Bs and Lb (Bc) Bs mixing (need ~ fb-1) Radiative B decays b→sγ (γ→ee) Sample for flavor tagging studies Selection 4 GeV e,m + 2 GeV SVT track Run I single 8 GeV e, m Lower B Et threshold Run1 10 GeV vs Run2 6 GeV ~ 3 x eSVT x Run I yield Radiative decays Large Run II inner material X2.5 gain in acceptance ~10 Bd ->K* γ / 100 pb-1 ~few Bs-> φγ / 100 pb-1

  19. Di-lepton Trigger • Physics Goals • B→ J/ψX • sin(2β), lifetimes • rare decays B→ll(X) • Selection • 1.5 GeV dimuon • 2 GeV dielectron • 2-3X Run I yield • Run I: 2 GeV muon, 5 GeV electron

  20. Charm Physics

  21. Charm Yields • Hadronic trigger gives large charm sample Large percentage of D’s from direct production With 2 fb-1 expect 10-100x samples of charm from Fixed Target experiments

  22. Charm Measurements • Physics Prospects • Production cross sections • for D0, D+, D*+,Ds, Λc • can separate prompt from direct production • Mass measurements • mDs - mD+ , for Ds, D+ →φπ • D0– D0 mixing search • CP Violation searches • Rare/Forbidden Decays

  23. B Physics Prospects J/ψ→µµ Sample • Collecting large sample of J/ψ, hadronic and semileptonic b decays (Quoted errors below assume 2fb-1) • Broad program of measurements • Lifetimes • Measure cτ with error of .01 ps B0 ,B+; .03 ps Bs ; .04ps Λb • b production • Δmd mixing measurement • b hadron masses • Branching ratios • Rare Decays • Bs ,Bc , Λb measurements unique to Tevatron

  24. B Prospects (cont) • Bs mixing • All pieces necessary for measurement are working • TOF, Hadronic trigger, SVX, L00 • Hadronic yields lower than expected • Working on improving trigger and reconstruction efficiency • sin(2β) from B→ J/ψKs • will collect large sample of events • Use J/ψ→µµ and ee modes • next step to optimize flavor tags • with 2fb-1 will have competitive measurement • σ sin(2β) ≈ 0.06

  25. Bs lifetime difference ΔΓs Use Bs→J/ψφ mode Fit lifetime and transversity angle of decay Separates CP even/odd states Error on ΔΓs/Γ of 0.05-0.08 CP asymmetry in B0→ππ Hadronic trigger collecting B0→hh sample Use PID to separate B→Kπ , B→KK Error on asymmetry of 0.09 γ from Bd→ππ , Bs→KK Difference in asymmetries only from CKM phases γ and β Assume SU(3) symmetry Uses simultaneous fit of time dependent asymmetry Expect σγ≈ 10° Requires measurement of β Search for CP violation in Bs→J/ψφ Asymmetry very small in Standard Model Test for new physics Error on asymmetry of 0.1 to 0.2 (depending on value of xs) B Prospects (cont)

  26. Summary • The CDF detector is working well and collecting data for physics • Hadronic trigger greatly extends B and Charm Physics capabilities • CDF will collect a very large Charm sample • Expect first charm measurements later this summer • Broad charm physics program for Run 2 • B physics program has all the pieces in place • B triggers collecting samples • Detector providing good reconstruction • Particle ID working for flavor tagging • Lots of interesting B measurements to come

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