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Heavy flavor results from CDF Run II Yuri Gotra University of Pittsburgh for the CDF Collaboration Deep Inelastic Scattering April 22-27, 2003 St Petersburg, Russia. Top Physics top production tt cross-section dilepton channel lepton + jets channel top mass Summary. Introduction

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  1. Heavy flavor results from CDF Run IIYuri Gotra University of Pittsburghfor the CDF CollaborationDeep Inelastic Scattering April 22-27, 2003St Petersburg, Russia

  2. Top Physics top production tt cross-section dilepton channel lepton + jets channel top mass Summary Introduction Bottom Physics Triggers and data samples Detector calibration B masses Lifetime: B0, B+, Bs J/yX Dimuon B decays Semileptonic B decays Two body Bhh decays Outline Yuri Gotra - DIS 2003

  3. B physics with Run II CDF Open wide spectrum of B hadrons • B, B0, Bs, Bc, b, b ...(unique) bb cross section is 50-100 mb ~O(105) larger than e+e-@(4S)/Z0 ~O(103) B’s per second at design luminosity (~10 B’s per second at (4S) factories) BUT: - B hadrons are hidden in a 103 larger background (inelastic(pp)  50 mb - Events more complicated than at (4S) • BRs for interesting processes: ~O(10-6) • S/B @ production (Tevatron): ~10-9 • S/B @ production (B factory): ~10-6 • Mean multiplicity of tracks/event: ~4 (4S) • Combinatoric background • - Events pile-up within the same beam crossing: problem for the trigger • - Typical S/B @ analysis level: ~O(0.5÷5) • B physics signatures: • QCD physics • - Quarkonium cross section and B fraction down to 0 GeV, polarization • - B cross section; fragmentation • CKM studies: CP violation and mixing • - Bs mixing, BsDs, lnDs • - |Vtd|: B0lnD • -DGs: BsJ/y , J/yh, lnDs, DsDs • - CP asymmetry: B0(Bs)hh • - : BsDsK+, BDK • - g:B0, BsKp, pp, KK • - b: B0J/yK0s • Properties of Bs, Bc, b, etc • - Production, mass, lifetime • Rare decays • - BK(*),B0, Bs • - Physics beyond the standard model: • Bse Solution: Vertex detector + trigger + Particle ID CDF CLEO Yuri Gotra - DIS 2003

  4. B Triggers and data samples Conventional New at CDF DiMuon (J/) 2 central muons PT() > 1.5 GeV Run I: > 2 GeV Trigger on J/ymm Collected ~ 70 pb-1 ~ 0.5MJ/ymm signal J/ modes down to low PT(J/)(~ 0 GeV) Displaced track + lepton (e, ) 1 muon/electron pT> 4 GeV 1 other track pT > 2 GeV SVT IP>120 mm M(l-Track) < 5 GeV Collected ~70 pb-1 ~ 0.5M BlX signal Semileptonic modes 2-Track Trig. 2 Tracks with pT > 2 GeV SVT IP > 120 mm pT1+pT2 > 5.5 GeV Collected ~70 pb-1~ 0.5M D0Kp signalFully hadronic modes • - BS mixing • CP asymmetry in 2-body charmless decays - CP violation - Masses, lifetimes - Quarkonia, rare decays • - High statistics lifetime • tagging studies, mixing Secondary Vertex B Decay Length Lxy PT(B)  5 GeV Primary Vertex d = impact parameter Lxy  450 m Yuri Gotra - DIS 2003

  5. Raw tracks Detector calibration:p scale & B-field correction MASS SCALE: MCDF = MPDG-M(PT) Use J/ to correct for B field and energy loss: (scale)/scale ~ 0.02% Sanity check with known signals: Add B scale correction 1S  Tune missing material Correct for material in GEANT 2S 3S Yuri Gotra - DIS 2003

  6. B masses in exclusive J/y channels M(Bs) is already the second best in the world (after CDF Run I) 18.4 pb-1 B0J/yK0* 18.4/pb Prerequisite:momentum scale was precisely set (@0.02%) using J/ sample (~200K events) BsJ/yf • BuJ/y K+ • BdJ/y K0*(K0*K+p -) • BsJ/y f (fK+K-) Very good S/B More mass plots CDF2 (MeV/c2) DM/sCDF sCDF/sPDG Bu 5280.6 ±1.7 ±1.1 +0.8 4.0 Bd5279.8 ±1.9 ±1.4 +0.24.8 Bs5360.3 ±3.8 ± 2.11.9 18.4 pb-1 BJ/yK Bu 2.1 2.9 • Statistics limited, but compare well w/PDG • Systematics already under control. • Precise measurements, soon! Yuri Gotra - DIS 2003

  7. Lxy B lifetimes (1) Crucial: precise Secondary Vertexing Silicon VerteX detector (SVX) c = Lxy /  PV  = PT(B) / M(B) CDF Run I:full set of precise B-lifetime meas. Competitive with LEP • Inclusive: BlDX, BJ/X • Large statistics, but… • Final state not fully reconstructed • PT(B) has to be corrected from MC • Exclusive: BsJ/, b J/ • Small systematics • Limited statistics Run II:x50 statistics( 2fb-1, wider silicon & lepton coverage, hadronic triggers) Improve measurements. Especially Bc, Bs, b down to ~0.01 ps Yuri Gotra - DIS 2003

  8. B lifetimes (2) Heavy Quark Expansion predicts lifetimes for different B hadron species t(Bc) << t(Xb0) ~ t(Lb) < t(B0) ~ t(Bs) < t(B-) < t(Xb-) < t(Wb) • t(B+)/t(B0) = 1.03÷1.07 • t(Bs)/t(B0) = 1.00±0.01 • t(Lb)/t(B0) = 0.9÷1.0 B+/B0 and Bs/B0 measurements agree with prediction Small discrepancy forLb lifetimes • LEP + CDF Run I Yuri Gotra - DIS 2003

  9. Inclusive B  J/y X Lifetime J/y B CDF July 2002 (18 pb-1): t=1.5260.0340.035 ps PDG 2002: t=1.6740.018 ps Inclusive B lifetime with J/y’s BJ/yX from ~ 28.000 J/y events c = J/y (prompt + non-prompt) + non-J/y c(B) = 458  10(stat)  11(syst) m PDG: 469 ± 4 μm Yuri Gotra - DIS 2003

  10. MB,pB m- LB K+ B+ m+ Exclusive BLifetimes B+gJ/y K+ B0gJ/y K0* (K0* g K+p-) BsgJ/yf(fgK+K-) Unique to Tevatron uncertainties @ Run I level • Simultaneous fitting of • MB: Extract signal fraction • c: Extract the lifetime • c = LB / pBx MBPDG = 0.89  0.15 = 1.11  0.09 Yuri Gotra - DIS 2003

  11. Background is subtracted Conventional way to B: J/y mm CDF triggers on stopped J/ymm: pT(m) 1.5 GeV/c, pT(J/y )  0 CDF can measure cross section down to pT = 0 (first at hadron collider) s(ppgJ/y; pT>0;|y|<0.6) = 240  1 (stat)  35/28 (syst) nb s(bJ/X): in progress Yuri Gotra - DIS 2003

  12. m m m Exclusive B  J/y Signals K+ K+ K+ K- Bs p- B0 B+ m m m B+gJ/y K+ ~ 640 signal events (>1000 events with loose selection) B0gJ/y K*0 (gKp) ~ 220 signal events Normalization mode for sin2banalysis BsgJ/yf (gKK) ~75 signal events Golden mode for DGsmeasurement Yuri Gotra - DIS 2003

  13. Lepton D B SVT track n P.V. B+/B0 from lepton+displaced track high statistics semileptonic B samples Excellent calibration samples for B+/B0lifetime, tagging and B0 mixing BglD0X (D0gKp):~10,000 events BglD*+X (D*+gD0p):~1,500 events BglD+X (D+gKpp):~5,000 events Run II yields significantly larger, lower lepton pT threshold possible thanks to i.p. trigger Yuri Gotra - DIS 2003

  14. Bs from lepton + displaced track BsDsl[] l[[KK] ]lONLY @ Tevatron Yield/Lumi ~ Run I x 3, S/N ~ Run I x 2 • HIGH STATISTICS SAMPLE: • Inclusive lifetime:  • Mixing (moderate xs): • good S/N, limited time resolution: back-up sample 385  22 Ds (muon only) Systematics of trigger bias Efficiency vs c ARBITRARY UNITS MC Lifetime: stat. ~ 0.07 ps (PDG:0.057 ps) Future: Bs mixing (low ms case) Yuri Gotra - DIS 2003

  15. bfrom lepton+displaced track Yield/Lumi = 4 x Run I, S/N ~ 2 x Run I bcl[pK]l • Branching Ratio • Measure  • Q2 = m(l) • important for theory • Experimental challenge: • disentangle from decays through excited baryons Time of flight dE/dx + Lifetime: stat. ~ 0.12 ps (PDG:0.08) Future: semileptonic form factor Yuri Gotra - DIS 2003

  16. Bc and b Lb  L+c l -n Lb J/y L (L p) Run I: ~20 eventsBcJ/ye/ Run I: M(Bc) = 6.400.390.13 GeV/c2 t(Bc) = 0.46 +0.18 0.03 ps t(Lb) = 1.32  0.15 0.07 ps -0.16 Run II data 53  11 65 pb-1 Lb J/y L Also hadronic modes: LbLc (Lc pK) LbpD0p(D0 K) LbpK / p Run II: better Mass, Lifetime, BR Also exclusive channels:BcJ/ p and fully hadronic:BcBsp Yuri Gotra - DIS 2003

  17. Physics with B0 h+h- 300 eventsin 65 pb-1: first charmless B’s at hadronic collider B0 h+h-is a mixture (1:4:2:0.5) of Bdpp;BdKp;BsKp;BsKK;tree, BR~5x10-6penguin, BR~1.5x10-5 • Strategy for disentangling channels: • Invariant mass shape (M ~25 MeV/c2) • Kinematical variables • Particle Identification • COT dE/dx • Oscillation of CP asymmetry ( inv.mass) CDF II simulation —sum BdK BsKK Bd BsK  • Can soon perform interesting measurements: • Relative B. Ratios: Bdpp/Kp; BsKK/Kp • Direct CP asymmetries in BdKp (self tagging) • CP asymmetries in Bdpp(with b-tagging) • Later on: CKM angle Yuri Gotra - DIS 2003

  18. Physics with the hadronic trigger open access to fully hadronic D and B signals D D D’s from Primary Vertex have d 0 B d(D) D-mesons Impact Parameter (d) used to discriminate the two components D mesons I.P. (d) distribution B fraction D0K16.4  0.7 % D*D011.4  1.4 % DK11.3  0.5 % Ds34.8  2.8 % Reconstructed large (0.5M) D mesons: D K, D0K, D*D0, Ds  D0KK, D0p Measured prompt D vs. Dfrom B Yuri Gotra - DIS 2003

  19. Physics with B0s J/ • largest fully reconstructed sample • in the world:7411 events • Yield/Lumi = 2 x RunI • Expected in 2 fb-1:  4000 events • CP asymmetry measures the weak phase of Vts (angles = 2s ) Expected to be very small in SM: s 2o sin(2s ) O(l2)  0.03 Complicated analysis: requires xsand angular analysis to disentangle CP even/odd final states CDF II reach : s(sin(2 s ))  0.1 with 2 fb–1 (0.03÷0.06 with 10 fb–1) • If asymmetry observed with 2fb–1 signal for NEW Physics • We also want to measure the lifetime difference between two Bs mass eigen states:s = BsH - BsL Current limit (LEP):s/s < 0.31 (S.M.:DG/G = 0.05 ÷ 0.20) • Expected uncertainty: (s/ s) = 0.05 Yuri Gotra - DIS 2003

  20. More BgJ/ysignals B0gJ/yK0s ~220 events B+gJ/yK+ • Two track trigger data (65 pb-1) • Reconstruct hadronic B decays • B+gJ/yK+(J/ygl+l-): 311±25 normalization mode First steps towards sin(2b) measurement Yuri Gotra - DIS 2003

  21. Hadronic bc signal bc[pK] 40 events in 65 pb-1,largest fully reconstructed hadronic channel NO PID YET pK Mass [GeV] • Measure mass, lifetime, polarization, t(Lb)/t(B0) • More channels to be added • LbgLcppp, pD0p • LcgLppp pK Mass [GeV] Yuri Gotra - DIS 2003

  22. Lxy c =  Ingredients for B0s mixing ms/md a Nunmix(t) – Nmix(t) Amix(t) = = Dcos(mst) g b Nunmix(t) + Nmix(t) • Reconstruct the final state(use fully rec. B0sD-s π+(3π)) with good S/B (thanks to precise tracking, vertexing, PID) ;  = PT(B) / M(B) 2. Measure proper decay time: Current limit: ms 14.4 ps-1 Error on B momentum, ~ 15% (semileptonic) negligible (~ 0.5%) for fully reconstructed final states 60 fs (SVX II detector) 45 fs (also Layer 00 is used) 3. Identify the flavor of Bsat production: B-flavor tagging algorithms Yuri Gotra - DIS 2003

  23. First steps towards B0s mixing Collect more data and understand tagging Bs Ds(*)  []   [[KK] ]  Fully reconstructed Bs is consistent with BdD-+control sample More channels to be added BsDs, DsK*K, K0sK,  Yuri Gotra - DIS 2003

  24. u W+ p+ b d B0 p u d d b ms/md a Angle  from B0h+h- g b B0 +has two (comparable) decay amplitudes: Penguin Tree W+ d p+ u u,c,t B0 g d u p d direct CP CP from mixing alone B0 + Bs K+K ACP(t) =ACPdircos(Dmd t) +ACPmixsin(Dmd t) ACPdir, ACPmixfunctions of,, d,(d ei P / Tdecay amplitude) R. Fleischer(PLB 459 (1999) 306):Assume U-spin symmetry (d  s) Similar relation holds for BsK+K(Dmdreplaced byDms) The 4 asymmetries: function of, and P/T amplitude ratio Parameters: from fit of meas. ofACP(t) for Bdand BsKK Expected (2fb-1) accuracy:() = ±10(stat) ±3(syst) (SU(3) breaking effects) Yuri Gotra - DIS 2003

  25. B physics prospects(with 2fb-1) Both competitive and complementary to B-factories The B physics potential is great and we expect: • Bs mixing:BsDsπ(Ds3π)(xs up to 60, with xd meas. one side of U.T.), direct and mixing asymmetries in two body decays • Angle :B0J/yKs(refine Run I measurement up to (sin2)  0.05) • CP violation, angle: B0ππ(πK), BsKK(Kπ), at ~10° possible • Angle sand s/s:BsJ/y(probe for New Physics) • Precise Lifetimes, Masses, BRfor all B-hadrons: Bs, Bc, b… (CDF observed: BcJ/y e(). Now hadronic channels BcBsX can be explored) • HF cross sections (beauty and charm) By the end of Run IIb (~2008): 5 the statistics of Run IIa ! • Stringent tests of SM … or evidence for new physics ! Yuri Gotra - DIS 2003

  26. Why do we care about Top? The Discovery of the top quark in 1995 was no big surprise. What was surprising is that its mass is almost 40 times that of the b quark, and tantalizingly close to the scale of EWSB. The Fermilab Tevatron has been the only place, and will be until the LHC turns on in ~2008, to study the top quark. Everything we know about top is based on ~100 events from the Tevatron Run I. • tt measurement: (Precision test of QCD, Probe for physics beyond SM) • Top mass: • Fundamental parameter of Standard Model (SM) • Affects predictions of SM via radiative corrections (BB mixing, W and Z mass, measurements of MW, mt constrains MH) • Large mass of top quark (Yukawa coupling  1, • may provide clues about electroweak symmetry • breaking) With 30 times more top events, as expected in Run IIa: • Why is top so heavy ? • Is it or the third generation special ? • Is top involved with EWSB ? • Is it connected to new physics ? Yuri Gotra - DIS 2003

  27. Production and Decay of Top Quark At the Tevatron, top quarks are primarily produced in pairs via strong interaction. Single production via weak interaction not yet observed ttop ~ 4 x 10-25 s L-1~ (100 MeV)-1 ~10-23 s Top decays as free quark! BR(tWb) @100% CDF Run I:Ldt 109 pb-1(~300 top candidates) Main “usable” top event topologies: Dilepton: tt  lnlnbb2 high-PT leptons, 2 bjets, large Missing ET (BR 5% e+m) Lepton + Jets:tt  lnqqbb1 high-PT lepton, 4 jets (2 b's), large missing ET (BR 30% e+m) All-hadronic:tt  qqqqbb6 jets (BR 44%) Yuri Gotra - DIS 2003

  28. µ2 µ1 - N N Jet1 obs bkg s = ( t t ) Jet2 × ò A L b l-  tt = 13.2  5.9stat  1.5sys  0.8lum pb NLO@ s=1.96 TeV for Mtop = 175 GeV: 6.70+0.71–0.88 pb p p b l+  stt:dilepton cross section • Event selection • 2 High PT (PT>20 GeV) oppositely charged leptons (e,m). • Both isolated: ICAL< 0.1 • Veto Z’s, cosmics, and conversions • Neutrinos: large missing ET > 25 GeV • at least 2 jets with ET > 10 GeV • Total transverse energy of the event > 200 GeV • BR~5%, detection efficiency ~ 11% • 5 candidate events in 72 pb-1 • (Run I: 9 events) tt = 8.2  4 pb • Backgrounds: Drell-Yan, Z0->tt, WW : 0.30±0.12 • Disadvantageslow yield, difficult to measure Mtop accurately • Advantageshigh S/B ~8 Yuri Gotra - DIS 2003

  29. b Jet3 Jet2 Lego view Jet1 Jet4 l-  p µ p tt = 5.3  1.9stat  0.8sys  0.3lum pb q b q stt: lepton + jets cross section • Event selection • One high momentum, central, isolated lepton, PT > 20 GeV/c, e or m. • Veto Z’s, cosmics, and conversions. • Neutrinos: large missing ET > 20 GeV • 3 or more jets with ET > 15 GeV • At least 1 jet with secondary vertex tag • 15 observed events in 57.5 pb-1 • Backgrounds from Wbb,Wcc, mistags, Wc, non-W (fake lepton): 3.8 ± 0.5 • Lower S/B1:6 for W+ 3 jets • b-tagging improves S/B3: • Higher statistics • Essential for Mtop (2 b-tags jets) Run 1 Run 2 Yuri Gotra - DIS 2003

  30. W+ b-jet n X t t jet W- jet b-jet Top mass: lepton + 4 jets • METHOD • Use 2C constrained fitting technique with constraints • m(ln) = m(qq) = mW • m(lnb) = m(qqb) • PDG: MW, W, t • 24 combinations: • 12 correspond to the jet-parton match • every combination has 2 solutions for neutrino PZ • Choose combination with lowest 2. • Improvements to DMtop: • Statistics: • Increased b-tag acceptance • events with b-tag reduce combinatorics • Choose best measured events • Jet Energy Scale: • Use control samples (Zbb, Wqq) to reduce systematics • Jet energy flow techniques 5 vertices 20 constraints Yuri Gotra - DIS 2003

  31. Top mass Run I CDF+D0 combined: mt=174.3 5.1 GeV/c2 dominated by jet energy measurement • Run 2a expectations: • DMtop = 2-3 GeV Use a continuous likelihood method to extract top mass and statistical uncertainty Mtop is the minimum of the log-likelihood distribution top corresponds to a change of 0.5 units in the log-likelihood Yuri Gotra - DIS 2003

  32. Physics with large top samples • top quark mass measurements (within 2-3 GeV/c2) • tt pair production cross section (within 8%) • single top production cross section • tt spin correlations, studies of top polarization • rapidity of tt system • mass of tt system • soft gluon radiation in tt events • W helicity in top decays • single top production  |Vtb| • any anomalies in the above studies • rare decays… • NEW PHYSICS ? ~800 b-tagged tt lepton+jets events in 2pb-1 • With larger samples (later this year) we will be able to extend our Run I searches for extensions to the SM Yuri Gotra - DIS 2003

  33. Summary Run II CDF collected ~100 pb-1 of data for heavy flavor physics (Run I total: 110 pb-1) • Detector is well calibrated, mass scales and vertexing resolution are understood, Run I physics signals are re-established. Some of the systematic uncertainties are still conservative. Will be reduced in future Impact parameter trigger: huge/clean semileptonic/all hadronic B signals • The SVT  great success: • unique @ hadron collider • CDF as Charm/B factory • Forward detectors  diffractive physics • Great heavy flavor physics potential, we have results on: • Masses, lifetimes, production cross sections competitive with Run I • We are preparing for high luminosity: • Promising perspectives for flagship analyses: studies of Bs, Bc, CP violation, Bs mixing, s, b, charmless B-decays and other topics unique to Tevatron are in progress. Lots of heavy flavors at CDF, stay tuned for new exiting results Yuri Gotra - DIS 2003

  34. Heavy flavor results from CDF Run II: B physics • Run II CDF collected ~100 pb-1 of data for heavy flavor physics • Masses, lifetimes, production cross sections competitive with Run I • studies of Bs, Bc, CP violation, Bs mixing, s, b etc are in progress Lepton + displaced track Two track trigger Dimuon trigger Bs lnDsX Lb Lcp Bs J/y f Lifetime Mass CDF2 (MeV/c2)sCDF/sPDG Bu 5280.6 ±1.7 ±1.1 4.0 Bd5279.8 ±1.9 ±1.4 4.8 Bs5360.3 ±3.8 ± 1.9 Yuri Gotra - DIS 2003

  35. Heavy flavor results from CDF Run II: top quark • We have reestablished the presence of the top quark in Run II • Cross sections in dilepton and lepton plus jets channels are in agreementwith the SM expectations • The tt events show mass compatible with the run I measurement • The Fermilab Tevatron has been the only place, and will be until the LHC turns on in ~2008, to study the top quark Dileptonstt = 13.2  5.9stat  1.5sys  0.8lum pb tt = 5.3  1.9stat  0.8sys  0.3lum pb Lepton plus jets Yuri Gotra - DIS 2003

  36. Backup Slides Yuri Gotra - DIS 2003

  37. Chicago  Booster CDF DØ Tevatron p source Main Injector (new) Our machinery at Fermilab Run II: proton-antiproton collisions ats=1.96 TeV Yuri Gotra - DIS 2003

  38. Jan 03 Mar 02 Tevatron p+p- collider Main Injector (new injection stage for Tevatron) Ability to accelerate and deliver higher intensity of protons More efficient anti-proton production Collision rate: 396 ns crossing time (36x36 bunches)  ~ 2M collisions/sec Center of Mass energy: 1.96 TeV CDF Integrated Luminosity 130 pb-1 (delivered) 100 pb-1 (to tape) B/Charm: ~ 70 pb-1 Today: luminosity ~4.0 x 1031cm-2s-1 4 to 7 pb-1/week delivered Goal: luminosity: ~1032 cm-2s-1 16 pb-1/week delivered In this talk: results with 70 pb-1 for CDF commiss Yuri Gotra - DIS 2003

  39. What is New at the Tevatron • Main Injector: new injection stage, more efficient anti-p transfer to Tevatron ring • Recycler: new storage ring for reuse anti-p (still commissioning, ready 2004) • Higher collision rate: 396ns crossing time (36x36 bunches) ( 132ns, 108x108) major upgrades in detector, electronics and trigger !!! • Slightly higher C.M. energy: 1.8  1.96 TeV • Higher Inst. Luminosity: 5-10 times higher than in Run 1 • Run plans: Run 2a: L = 5-8  1031cm2 s1 • (L = 10-20  1031cm2 s1 , with Recycler) • Total integrated L = 2fb1 • Run 2b: Total integrated L = 6 - 10fb1 2005 …2008 Yuri Gotra - DIS 2003

  40. Tevatron status andgoals 10–6f 0B NpNpb(6 r r) L H ( l /  *) (1031 cm-2s-1) = 2 *( p+  pb) Accelerator parameters: Integrated Luminosity (fb-1) Yuri Gotra - DIS 2003

  41. 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 Yuri Gotra - DIS 2003

  42. Yuri Gotra - DIS 2003

  43. CDF Detector overview CDF Detector Overview New Central Tracker (COT) ToF counter for K/p separation Placed right before the Solenoid New Plug Calorimeter 1.3 < |h| < 3.5 Muon Detector More Coverage SVX: Acceptance increase |z0| < 30 g 45 cm L00: Vertex resolution ISL: |h| < 2.0 Forward Calorimeter 3.5 < |h| < 5.1 Yuri Gotra - DIS 2003

  44. CDF Detector in Run II Inherited from Run I: Central Calorimeter (||<1) Solenoid (1.4T) Partially New: Muon system(extended to ||~1.5) Completely New: Tracking System - 3D Silicon Tracker(up to ||~2) - Faster Drift Chamber Time-of-Flight(particle ID) Plug and Forward Calorimeters DAQ & Trigger system(Online Silicon Vertex Tracker: trigger on displaced vertices, first time at hadron collider) Yuri Gotra - DIS 2003

  45. 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 Layer 00) LAYER 00: 1 layer of radiation-hard silicon at very small radius (1.5 cm) (achievable: 45 fs proper time resolution inBsDsp ) Yuri Gotra - DIS 2003

  46. 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 Yuri Gotra - DIS 2003

  47. Crossing: 396 ns: 2.5 MHz Level 1: hardware Calorimeter, Muon, Track 15kHz (reduction ~x200) Level 2: hardware + CPU Cal cluster, Silicon track 300 Hz (reduction ~x5) Level 3: Linux PC farm ~ Offline quantities 50 Hz (reduction ~ x6) CDF Trigger System Overview Yuri Gotra - DIS 2003

  48. Level 2: Silicon Vertex Trigger Use silicon detector information Good IP resolution Trigger on displaced track beamline reconstruction update every ~ 30 seconds IP resolution: ~ 50 mm 35mm beam size + 35mm SVT Increase physics sensitivity of the Run II CDF CDF as “Charm Factory” Millions of D’s per 100 pb-1 Collect Hadronic B sample No Lepton required in final state Bs physics (mixing in Dsp) Higgs/new particles decaying heavy (b and c) quarks f z Silicon Vertex Tracker (SVT) Yuri Gotra - DIS 2003

  49. 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 Yuri Gotra - DIS 2003

  50. B triggers: conventional Needspecialized triggers (bb) /(pp)  10-3 CDF Run I, 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 I: 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 Yuri Gotra - DIS 2003

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