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Current results and future prospects at Tevatron

Current results and future prospects at Tevatron. T. Maruyama 　（ Univ. of Tsukuba ） For CDF / D0 collaborations. Contents Recent status and plan of Tevatron Physics program at Tevatron by 2009 shutdown Recent physics results and prospects (1) Top and indirect Higgs search

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Current results and future prospects at Tevatron

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  1. Current results and future prospects at Tevatron T. Maruyama　（Univ. of Tsukuba） For CDF / D0 collaborations • Contents • Recent status and plan of Tevatron • Physics program at Tevatron by 2009 shutdown • Recent physics results and prospects • (1) Top and indirect Higgs search • (2) direct Higgs search • (3) flavor sector • Summary WHEPP 9

  2. CDF / D0 collaborations CDF Collaboration (12 countries, ~600 authors) Compact collaborations ! (compared to LHC) WHEPP 9

  3. 2.8 2.4 WHEPP 9

  4. Tevatron complex in Run II Recycler: ring to reuse the pbar which did not interact to proton. Electron cooling: electron is to run parallel to beam to make beam emittance smaller. Tev: 36 X 36 bunch colliding • p – p collisions at s = 1.96 TeV. • Peak luminosity 1.71032 cm-2 s-1. • precycler is being used as p stacking recently. (not for recycler) ： success!! • Electron cooling was successfully installed for shots to Tevatron. (Obtaining smaller beam emittance, We will see difference more in future.) • Designed (in 2004) luminosity was delivered successfully in FY05. WHEPP 9

  5. FY05 FY04 FY03 FY02 Data delivered to date 1.44 fb-1delivered, 1.15 fb-1 on tape (CDF) (80% data taking eff. - 20% ineff. Includes ~5% Trigger/DAQ dead time) 1.0 fb-1good for physics without silicon, 0.9 fb-1 good for physics with silicon D0 has similar amount of the data in the tape! WHEPP 9

  6. 9 8 7 6 5 4 3 2 1 0 End FY09: Double data up to FY07 30 mA/hr 25 mA/hr 20 mA/hr 15 mA/hr End FY07: Double data up to FY06 Integrated Luminosity (fb-1) End FY06: Double data up to FY05 End FY05: Double data up to FY04 9/30/03 9/30/04 9/30/05 9/30/06 9/30/07 9/30/08 9/30/09 Projected Data Sample Growth WHEPP 9

  7. Performance of Tevatron Real peak luminosity upto Sep-2005 FY02 FY03 FY04 FY05 100E30 100E30 Sep-2005 Sep-2005 Sep-2009 Designed peak luminosity to obtain 8.5 fb-1 400 pb-1 Tevatron is working well !! Integrated luminosity in FY05 Red : designed, blue : base (min.) WHEPP 9

  8. DAQ / Trigger Specifications (CDF case) * Run IIa L1 Accept not achieved due to higher than specified Silicon Readout and L2 Trigger execution times. ** Assume ~5% from readout and ~5% from L2 processing Triggers (Run IIb) for W, Z, Top, WH, ZH, H->WW, SUSY (partial), LED, Z’ ~50% of bandwidth at 3x1032 cm-2s-1 Studying further improvement WHEPP 9

  9. High Lum. Impact on Reconstruction / Physics 0.2 x 1032 cm-2s-1 1.0 x 1032 cm-2s-1 2.0 x 1032 cm-2s-1 3.0 x 1032 cm-2s-1 MTW • Analysis Techniques • W Mass (example) At higher inst. luminosity, there should be more # of inelastic interactions at each bunch, so we expect missing ET can be skewed.  Using lepton PT would give smaller systematic uncertainty than that using traditional transverse mass. pTlepton WHEPP 9

  10. Physics program of Tevatron before shutdown • Tevatron Shutdown：　2009 (2008?) What are the interesting Tevatron physics topics under running of the LHC? • How do we reduce the time rug between provided luminosity and that used in analysis?（Integrated luminosity is 1.1fb-1 now, while CDF uses ~0.7fb-1 in winter ） • What are the main physics programs? (related to trigger) example flavor sector: BS mixing ： DmS / Dmd rare decay : BS mm etc electroweak sector + top :W mass top mass Higgs Boson search New Physics search : non-SM Higgs SUSY, extra dim., compositenessetc. WHEPP 9

  11. top and indirect Higgs search WHEPP 9

  12. Indirect Higgs mass search with Mtop and MW • Higgs mass can be constrained from precise W mass and top quark mass measurements using the formula above (radiative correction). Also sensitive to new physics if loop exists. • Current CDF Run II best single measurement  173.5+3.9-3.8GeV/c2 and all combined value (Run I+Run II, CDF+D0, pick up best meas. in each channels)  172.7 2.9 GeV/c2 • Current best MW is inferred by LEP2 (80.392 0.039 GeV/c2), and world average is 80.410 0.032 GeV/c2. • Best Higgs mass  91+45-32 GeV/c2 and upper limit 186 GeV/c2 @ 95% C.L. WHEPP 9 Old : result in 2004

  13. CDF-I l+j Combination of top mass measurements Use only best analyses from each decay mode, each experiment. Both Ws -> ln (dilepton: 5%) One W->2jets / one W->ln (lepton+jets : 30%) Both Ws -> 2 jets (all had: 44%) All systematic uncerainty correlations are taken into account as properly as possible!! (statistically independent) Run I (~100pb-1) Run II(~350pb-1) WHEPP 9

  14. Basic improvement by 1/L - L0.7fb-1 in this winter. - Further improvement on JES by direct b-jet JES calibration by Z  bbevents. Current b-jet JES taken same as generic jet + additional uncertainty according to LEP/SLD measurements. Sig./Bkgd. Modeling (ISR/FSR/Q2 dependence etc.) can be improved by using our own data. Measurement in All Hadronic mode is coming soon. Future Improvement Combined Result: WHEPP 9

  15. New Method to constrain Jet Energy Scale W+ b-jet n t t jet W- jet b-jet • Use W2 jets to calibrate Jet Energy Scale (fully in situ). This scale is applied to b-jets and light-quark jets. • Do a cross-check for our standard JES calibration obtained in dijet, photon+jet environment. • Two dimensional fit for JES and Mtop simultaneously. Mjj(W) This method makes the largest systematic uncertainty as statistical issue !! We will achieve uncertainty Mtop ~ 2 GeV/c2 w/o no improvement at 2 fb-1. (note: this is only single measurement at CDF) WHEPP 9

  16. Results on the JESfrom the 2D Fit 2 b-tag jets sample 1 b-tag jets 4 high ET jets Variation of Mjj as a func. of JES (s ~3 GeV/c2) Data Mjj 1 b-tag jets 3 high 1 loose 0 b-tag jets JES (s) Mtop = 173.5+2.7-2.6(stat) 2.8 (syst) GeV/c2 = 173.5+3.9-3.8 GeV/c2 Result of 2D fit WHEPP 9 Mtop (GeV/c2) PRL / PRD accepted ( to be published )

  17. Summary of Top Mass Measurements Many cross-checks, combined best ones from each channels WHEPP 9

  18. J/+- mass vs 1/pT p / p p / p = - 0.0010 ± 0.0001 W mass status (CDF) Chamber wire positions: aligned <10 m Passive material between IP and COT: x-ray using  e+e-, check e’s E/p tail Momentum scale: J/ mass, check Upsilon and Z mass Energy scale: e’s E/p peak, check Z mass Uncertainty on MW: total 76MeV/c2 : 85, e: 105 MeV/c2 center value is still blinded. E / p of W electrons WHEPP 9 1 / pT(GeV-1)

  19. MW [MeV] MTop [GeV] MHiggs / Mhiggs [%] 10-1 1 10 10-2 10-1 1 10 Luminosity/Experiment [fb-1] Luminosity/Experiment [fb-1] Luminosity/ Experiment [fb-1] Electroweak Projections 3 2 50 WHEPP 9

  20. W helicity Top Mass l+ Top Width Anomalous Couplings Production cross-section Top Spin W+ CP violation Top Charge Resonance production p n t b Production kinematics _ b X _ Top Spin Polarization _ q’ t q Rare/non SM Decays W- _ p Branching Ratios |Vtb| Other Top Quark Properties • Understanding on top quark profile will be significantly improved by statistics in next a few years. • Any significant deviation from standard model prediction could indicate new physics. e.g. cross section is sensitive to production and decay anomaly. WHEPP 9

  21. Does something new produce ttbar? • Search for new massive resonance decaying to top pairs • Constraint top mass = 175GeV/c2 • D0 uses lepton+≥4jets (b-tag) with traditional kinematic fitter, while CDF uses lepton+=4jets (no-btag) with matrix element technique. • Fix most of SM backgrounds to expected rate • Use theory prediction of 6.7pb for SM top pair production Interesting fluctuation in both experiments double stat. in winter WHEPP 9

  22. Direct Higgs search WHEPP 9

  23. Standard Model Higgs Integrated luminosity (/fb) • Precision data prefer light SM Higgs • SUSY requires light Higgs. • studies in 1999 and 2003 predicted consistent result: • 2 fb-1: 95%CL exclusion at mH=115 GeV/c2 • 5 fb-1: 3s evidence at mH=115 GeV/c2 • If Higgs mass is small, TeV could compete. WHEPP 9

  24. Direct Higgs Search Both CDF and D0 have started the hunt WHEPP 9

  25. WHEPP 9

  26. How Do We Get There? • Assume current analyses as starting point • Factor = 2003 Higgs sensitivity study / current analyses • Reevaluated all improvements using latest knowledge Expect factor ~10 improvements and CDF+DØ combination WHEPP 9

  27. Improvement example: Lepton Selection • Forward leptons: factor 1.3 • Current analyses use only up to ||<1.1 • Electrons: • CDF: • Forward electrons used already by other analyses, e.g. W charge asymmetry • Up to ||<2.8 • Central electrons: recently improved efficiency from 80% to 90% • Factor 1.34 in acceptance • Muons: • CDF: uses only up to |h|<1.0 can be extended since we have detector. W electron charge asymmetry PRD 71, 051104 (2005) ~75% efficiency 35 < ETelectron < 45 GeV WHEPP 9

  28. 0.2 1.0 0 Mhiggs = 120 GeV Raw 0 50 100 150 200 250 0.2 1.0 0 Scale Corrections Resolution Improvements 0 50 100 150 200 250 EJet Scale & Resolution: Status / Improvements • Jet energy scale uncertainty: • precision measurements (Mtop), searches • now ~2.5% uncertainty for jets in top decays • further improvements: • generators, higher order QCD • better scale for ET > 100 GeV region • complete by end of this year • Jet energy resolution: • currently 17%, goal 10-11% • further improvements: • combine track, calorimeter Info: 2% • expand cone size: 2% • b-jet specific corrections:1-2% • sophisticated algorithms: 1-2% • complete by spring 2006 H --> bb mass (GeV) WHEPP 9

  29. Non-SM Higgs: Abb and Att • Supersymmetry (MSSM): • 2 Higgs doublets => 5 Higgs bosons: h, H, A, H± • High tanb: • A degenerate in mass with h or H • Cross sections enhanced with tan2b due to enhanced coupling to down-type quarks • Decay into either tt or bb: • BR(A tt) ≈ 10%, BR(A bb) ≈ 90% • Exact values depend on SUSY parameter space • Experimentally: • pp  Ab+X  bbb+X • pp  A+X tt +X • C. Balazs, J.L.Diaz-Cruz, H.J.He, T.Tait and C.P. Yuan, PRD 59, 055016 (1999) • M.Carena, S.Mrenna and C.Wagner, PRD 60, 075010 (1999) • M.Carena, S.Mrenna and C.Wagner, PRD 62, 055008 (2000) WHEPP 9

  30. MSSM Higgs Searches Accepted by PRL, hep-ex/0508051 || = 200 GeV M2 = 200 GeV Mgluino = 0.8 MSUSY MSUSY = 1 TeV, Xt = √6 MSUSY (mhmax) MSUSY = 2 TeV, Xt = 0 (no-mixing) CDF Preliminary 310 pb-1 WHEPP 9

  31. Flavor sector WHEPP 9

  32. 0 0 BS – BS mixing: Motivation Measure side of unitarity triangle: Dms / Dmd B mixing : box diagram within SM taking ratio : to reduce theoretical uncertainties • Yellow Band: Dmd measurement: ~15% uncertainty • Orange Band: Lower limit on Dms = Upper Limit on |Vtd| • The lower limit on Dms already gives a constraint to the Triangle • CKM Fit result: Dms: 18.3+6.5-1.5 (1s)： 2005 EPS from Dmd from Dmd/Dms Lower limit on Dms WHEPP 9

  33. + p Bs Mixing Analysis: Winter 2005 ~900 signal events with Bs Ds, Dsl where Ds K*K,  With 355 pb-1 CDF 95%CL Limit: 7.9 ps-1 CDF Sensitivity 8.4 ps-1 526 ± 33 events WHEPP 9

  34. Bs Mixing Analysis: Fall 2005 • Hadronic modes • Improved tagger (larger B0 calibration sample, NN for jet charge) • Improved primary vertex (event-by-event reco., most inner Si layer added, better track resolution understandings ) • Added a new decay mode Bs DS 3p (20% increase) • Semileptonic modes • SVT 2-track trigger - greater than x2 With 355 pb-1 CDF 95%CL Limit: 8.6 ps-1 CDF Sensitivity 13.0 ps-1 CDF Preliminary CDF Preliminary WHEPP 9

  35. 95% CL Exclusion 5 Observation Stretched Stretched Fall 2005 Fall 2005 Baseline Baseline Winter 2005 Winter 2005 Scale to Current Yield Scale to Current Yield 0.4 fb-1 4 fb-1 8 fb-1 luminosity / experiment [fb-1] 0.4 fb-1 4 fb-1 8 fb-1 luminosity / experiment [fb-1] ms Sensitivity Projections WHEPP 9

  36. Rare Decay: Bsm+m- SM prediction (highly suppressed) : Expected #signal = 0, any signal would indicate new physics (Buchalla & Buras, Misiak & Urban) e.g. SUSY may enhance the rate : (Babu, Kolda: hep-ph/9909476+ many more) CDF results : 0 event was observed, corrsponding to Br < 1.6 x 10-7 WHEPP 9

  37. Rare Decay: Bsm+m-（２） • Projected reach (assuming no improvements to current analyses): • Exclusion at 90% C.L.: • 4 fb-1: BR < 4 x 10-8 • 8 fb-1: BR < 2 x 10-8 • Discovery at 5s: • 4 fb-1: BR = 1 x10-7 • 8 fb-1: BR = 7 x10-8 • ATLAS (SN-ATLAS-2003-003): • 5s discovery with L=1 fb-1 if Br=5x10-8 • 5s discovery with L=300 fb-1 for SM value ATLAS WHEPP 9

  38. b0 J/0 Bc0 J/e Lifetimes CDF Preliminary 360 pb-1 CDF Preliminary 370 pb-1  = 1.45 ± 0.13 ± 0.02 ps Single best measurement in a fully reconstructed decay mode  = 0.474 +0.073-0.066 ± 0.033 ps World’s best TeV is making competitive and world leading measurements for all the heavier B hadrons. WHEPP 9

  39. u d p c c b c Bc J/y Observation of Bc J With 0.8 fb-1, CDF M(Bc) = 6275.2 ± 4.3 (stat.) ± 2.5 (syst.) MeV Lattice QCD Cal. M(Bc) = 6304 ± 12 +18-0 MeV [hep-lat/0411027] Used data up to Sept.4, 2005 and approved as of Nov.10, 2005. Demonstrates physics results with data through Feb.05 by next summer. WHEPP 9

  40. So much more !! (but no enough time to show) Missing ET vs DF (WW) ttbar cross secton Jet PT spectrum Charged Higgs excluded region LQ search Q・h for single top cosq for W helicity Anomalouscoupling of Wg BC meas. (J/Yp) Z’ search W’ search g ET of Wg WHEPP 9

  41. Summary • Tevatron is delivering good luminosity with almost same level as designed one. • For higher luminosity in near future, CDF/D0 should consider trigger and physics impact. • CDF and D0 are thinking on what are meaningful physics programs during running of LHC programs. • Core physics programs such as top mass has good shape and perspectives. (Tevatron average already gives the uncertainty by 2.9 GeV/c2 at ~350 pb-1) • To achieve the sensitivity study in 2003, some significant improvements is needed for Higgs search. CDF / D0 are making effort to achieve it. TeV is producing impressive and important results!! WHEPP 9

  42. Backup slides WHEPP 9

  43. CDF at Tevatron SVX EM cal Muon Had cal Multi-purpose detector: precision meas. & search for new physics polar angle  • Silicon detector (SVX): • top event b-tag:~ 60% • COT: drift chamber • Coverage: |h|<1 • sPt / Pt ~ 0.15% PT • Calorimeters: • Central, wall, plug • Coverage: |h|<3.6 • EM:sE / E ~ 14% /ÖE • HAD:sE / E ~ 80% /ÖE • Muon: scintillator+chamber • muon ID up-to |h|=1.5 COT:tracking WHEPP 9

  44. B Tagging (secondary vertex) Hadronic Tau Tagging Evisible > 30 GeV ~50% efficient <0.5% mis-identified Tagging and Jet Energy Calibration Better algorithms: Neural Network Forward Jet mis-id (%) efficiency (%) Loose (1.8% mistag) Tight (0.6% mistag) E/E ~ 3% at 50 GeV ~xx% at 100 GeV ~xx% at 200 GeV Submitted to NIM WHEPP 9

  45. Top Mass vs ttbar cross section WHEPP 9

  46. Zbb Trigger : • 2 SVT track + 2 10GeV clusters. Offline Cuts : • N==2 jets w/ ET>20GeV, |h|<1.5 (JetClu cone 0.7). • Both jets are required to have secondary vertex tag. • Df(j1,j2)>3.0. • ET3rd-jet<10GeV. WHEPP 9

  47. MSSM Higgs: Present and Future • Current data (310 pb-1) has no excess Sensitivity different in other regions of parameter space • Close gap to LEP with increasing datasets • tanb=40≈mtop/mb reached for mA<240 GeV/c2 WHEPP 9

  48. New Phenomena Searches X e+e- searches (paper in preparation) X top pair resonance searches (paper in preparation) Z’ in ee CDF Preliminary 448 pb-1 Mee (GeV/c2) CDF Preliminary 319 pb-1 Projections WHEPP 9

  49. Combination of top mass measurements Both Ws -> ln (dilepton: 5%) One W->2jets / one W->ln (lepton+jets : 30%) Both Ws -> 2 jets (all had: 44%) Use only best analyses from each decay mode, each experiment. • Correlation : • uncorrelated • stat. • fit method • in situ JetEnergyScale(JES) • 100% w/i exp(same period) • JES due to calorimeter • 100% w/i channel • bkgd. model • 100% w/i all • JES due to fragmentation, • signal model • MC generator Run I (~100pb-1) Run II(~350pb-1) WHEPP 9

  50. What if this were the only Mtop msmt? WHEPP 9

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