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Flavour studies and searches at the Tevatron

Flavour studies and searches at the Tevatron. at "Flavour in the era of the LHC". Nov 8, 2005. Rolf Oldeman University of Liverpool for the CDF and D0 collaborations. The Tevatron. 6.2km  396 ns bunch spacing Run I: 1989-1995 Run II: 2001-2009. Tevatron luminosity. Expect 4-8fb -1

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Flavour studies and searches at the Tevatron

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  1. Flavour studies and searches at the Tevatron at "Flavour in the era of the LHC" Nov 8, 2005 Rolf Oldeman University of Liverpool for the CDF and D0 collaborations Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  2. The Tevatron • 6.2km  • 396 ns bunch spacing • Run I: 1989-1995 • Run II: 2001-2009 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  3. Tevatron luminosity Expect 4-8fb-1 by 2009 already 5 overlapping collisions per bunch crossing Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  4. The Tevatron detectors • 4 general purpose detectors • superconducting solenoids • silicon vertex detectors • Excellent calorimetry • Wide muon coverage • Excellent momentum resolution • High-bandwidth trigger Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  5. Triggering at hadron colliders The trigger is the key to flavour physics at hadron colliders CDF Detector Hardware tracking for pT1.5 GeV 1.7 MHz crossing rate Muon-track matching 42 L1 buffers Dedicated hardware L1 trigger Electron-track matching Missing ET, sum-ET 25 kHz L1 accept Silicon tracking Hardware + Linux PC's 4 L2 buffers L2 trigger Jet finding Refined electron/photon finding 500 Hz L2 accept Linux farm (200) L3 farm Full event reconstruction 100 Hz L3 accept disk/tape Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  6. Overview • Charm physics • J/, open charm • Beauty physics • Bc, Rare decays, Bs mixing • Top physics • Production, mass, decays • Direct searches • SUSY, leptoquarks Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  7. Physics with J/'s J/+- easy trigger signature CDF and D0 collected millions • extensively used for • momentum calibration • muon trigger efficiencies • tracking calibrations CDF 220pb-1 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  8. The X(3872) Does not fit any cc state. Is it a D0D*0 'molecule'? Is it a ccg 'hybrid' D0 • 2003: Belle finds new narrow state XJ/+- • Quickly confirmed & studied by CDF and D0 m - m(J) = 774.9±3.1±4.0 MeV m = 3871.3±0.7±0.4 MeV • X behaves like ' • pT spectrum •  spectrum • prompt/b ratio • helicity angles • isolation m(+-) spectrum consistent with XJ/ Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  9. Open charm Large, clean charm samples can be recorded at a hadron collider with a displaced track trigger: CDF 5.8pb-1 Cross-sections agree with theory (FONLL) Cacciari, Nason JHEP 0309:006,2003 CDF put stringent limits on direct CP violation in D0 decays Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  10. New CDF 350pb-1 D0K+- analysis • 'Wrong sign' D0K+- decay • Double Cabibbo suppressed decays • D0-D0 mixing. Next step: time dependent mixing analysis Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  11. B physics at hadron colliders Phys.Rev.Lett. 68, 3403 (1992) has come a long way • From the first B+J/ K+ in CDF Run I • 2.6 pb-1 • no silicon detector • To precision measurements by CDF and D0 • all know B-hadrons: B+, B0, Bs Bc, b • a myriad of decay modes: • J/ modes e.g. BcJ/ • leptonic e.g. Bs+- • semi-leptonic e.g. BsDs • hadronic e.g. BsDs • charmless e.g. B0+- Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  12. Bc the last weakly decaying meson D0: Lifetime and mass in Bc J/ CDF: Evidence for BcJ/+ D0 210pb-1 <10-3 experiments give false positive result at this level New! CDF 360pb-1 Bc J/e: =(0.470.070.03)ps Agrees with lattice QCD predictions Bc has charm-like lifetime Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  13. Bs+- Standard model prediction: Br(Bs+-)= (3.50.9) 10-9 MSUGRA prediction: Dedes, Dreiner, Nierste PRL87:251804,2001 SUSY contribution M0 [GeV] Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  14. Find a Bs+- in 1012 collisions? CDF 360 pb-1 300pb-1 combine discriminating variables into a single likelihood ratio invariant mass lifetime Bs+- <2.010-7 isolation pointing angle Bs+- <3.910-7 • Combined limit: • Bs+- <1.510-7 • hep-ex/0508058 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  15. implications of Bs+-<1.510-7 Excluded! M0 [GeV] Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  16. Bd and Bs oscillations u, c, t b d Bd Bd W W b d u,c,t u, c, t b s Bs Bs W W b s u,c,t • Bd mixing  Vtd2 • slow: • md=0.5020.007ps-1 • large mixing phase: • sin2=0.7360.049 • Bs mixing  Vts2 • fast: • ms18ps-1? • small mixing phase: • sin2s0.02? Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  17. New physics in Bs oscillations b s Z' s b • Heavy Z' with FCNC. Barger, Chiang, Jiang, Langacker Phys.Lett.B596:229-239,2004 phase magnitude Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  18. Bs oscillations Pre-RunII world average includes LEP, SLC, CDF-RunI ms >14.5ps-1, sensitivity 18.3ps-1 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  19. Bs mixing – the D0 analysis Very efficient low-pT muon trigger BsDs, DsK-K++, selecting  and K*0 resonances combine opposite side muon, electron, jet charge: D2=2.170.130.08% ms >7.3ps-1, sensitivity 9.5ps-1 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  20. Bs mixing – the CDF analysis fully hadronic better(ct) semileponic BsDsl larger yields • Includes: • BsDs, BsDs • DsKK,Ds D2=1.550.09% ms >8.6ps-1, sensitivity 13.0ps-1 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  21. New world average limit 14.5  16.6 ps-1 sensitivity 18.3  20.0 ps-1 • Further improvements from • more data • more decay channels (e.g. BsDs*) • Same-side and opposite-side kaon tags Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  22. Top physics 5 orders of magnitude Most massive fundamental particle. Discovered only 10 years ago at the Tevatron! Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  23. top physics at the Tevatron SM: tt pair production, Br(tbW)=100% dilepton (4/81) 2 leptons + 2 jets + missing ET l+jets (24/81) 1 lepton + 4 jets + missing ET fully hadronic (36/81) 6 jets tag one or both b-jets Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  24. tt cross-section • tt production cross-section agrees • between both experiments • in all channels • with the theoretical prediction! Χ2/dof=4.3/5 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  25. The mass of the top quark top, Higgs and new physics give radiative corrections to mW mt and mW constrain mH Tevatron Run I + LEP2 results favoured light Higgs • Experimental challenges: • Missing neutrino • Jet energy scale (JES) • Understanding backgrounds hep-ph 0412214 Heinemeyer, Hollik, Weiglein Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  26. D0 Run II l+jets 320pb-1 'Matrix-element method' : All kinematic variables used in likelihood fit Jet Energy scale determined from hadronic W decays in the tt sample itself. cross-check with external calibration Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  27. CDF Run II l+jets 320pb-1 Template method: Compare reconstructed t,W mass to distributions from MC Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  28. Tevatron combined top mass details in hep-ex/050791 • Includes 8 measurements • from Run I and Run II, • from D0 and CDF • di-lepton, l+jet, fully-had Correlations taken into account Dominated by CDF and D0 Run II l+jet 172.72.9GeV Lower than but consistent with Run I average 178.04.3GeV Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  29. Implication of new top mass Standard model interpretation: Light Higgs favoured But LEP2 excludes m(H)<114GeV BSM interpretation: SUSY favoured over SM New Tevatron top mass pushes EW fit further towards light Higgs/SUSY! Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  30. Beyond masses and cross-sections W helicity l+ Top Width Anomalous Couplings Production cross-section Top Spin W+ CP violation Top Charge Resonance production p n b t b q’ Production kinematics _ X _ Top Spin Polarization _ p t q Rare/non SM Decays W- _ Branching Ratios |Vtb| Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  31. top decays to non-b jet • method: • Select tt events without requiring b-tags • Compare 0/1/2 b tags Measuring R=BR(tWb)/BR(tWq) Unitarity of the CKM matrix predicts R = 0.999999 a 4th generation can change this prediction D0 230pb-1: CDF 161 pb-1: Both experiments confirm within 20%: All jets from tWq decays are b-jets Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  32. t bH+ in MSSM • tH+b can compete with tW+b in MSSM • H+t*b, cs, , Wh0 • analyse (tt) • "dilepton" , • "lepton + jets" 1 b-tag • "lepton + jets" 2 b-tag • "lepton + hadronic " exclude MSSM phase space exclude tbH+ assuming H+ Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  33. Direct searches for BSM flavour • Leptoquarks • Exited leptons • Scalar quarks and leptons Typical signature: e, , , b-jet + jet, , or missing ET Most models require pair-production  even more distinct signatures! Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  34. Leptoquarks Carry both quark and lepton number Most GUT's predict Lepto-quarks strongly produced in pairs key parameter:  =1.0 : LQLQ  qql+l-  =0.5 : LQLQ  qql+l- (25%) qql (50%) qq (25%)  =0.0 : LQLQ  qq 1st generation: LQ1 qe / qe 2nd generation: LQ2 q / q 3rd generation: LQ3 q / q Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  35. 1st and 2nd gen. leptoquark results  pT(1)+pT(2)+ET(jet1)+ET(jet2) (GeV)  CDF 200 pb-1 1st gen. 2nd gen. 1st and 2nd generation leptoquarks excluded up to m120GeV( =0) to m250GeV( =1) Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  36. 3rd generation leptoquarks Z+- control sample Signature: 2 b-jet + 2 same signature as RP-violating stop! • CDF 320 pb-1 analysis: • 1 lepton, 1 hadrons. • No b-tag applied to jets -identification at hadron colliders works! m(LQ3)>155GeV for  =1 less strict then for 1st and 2nd generation leptoquark Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  37. Excited leptons Signature: 2 leptons + photon contact interaction gauge mediated similar limits on e* Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  38. Scalar quarks (SUSY) 'Classic' inclusive signature: jets + missing transverse energy ~ ~ Inspired by MSUGRA models: qq0, or gqq0 0 is stable, neutral, weakly interacting  missing ET ~~  (qq)  NflavNcol large cross-section, relatively clean signature  very large mass range 2jet+missing ET 3jet+missing ET 4jet+missing ET Important background: Z+jets, Z Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  39. D0 squark/gluino search Indirect limit from LEP2 (in SUGRA, m(g)  3m ~ MET>75 GeV MET>175 GeV 4 jets Main BG: tt expect: 7.10.9 observe: 10 HT>325 GeV 2 jets Main BG: Z+2 j expect: 12.85.4 observe: 12 3 jets Main BG: W+2j expect: 6.331 observe: 5 tan=3, A0=0, <0 Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  40. Conclusions • Tevatron has achieved an extremely rich flavour program:  charm  beauty  top  exotic • Possible thanks to versatile general-purpose detectors: • tracking with high pT resolution • electon, muon and photon identification • large trigger bandwidth • Expect first 1fb-1 analyses this winter Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  41. BACKUP Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  42. Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  43. Lifetime difference in BsJ/  • Both the J/ and the  are vector-mesons • spin 1  polarization degree of freedom • Three components in VV final state: • A0 : longitudinal component CP even • A║ : transverse parallel component CP even • A┴ : transverse perpendicular comp. CP odd • Standard model prediction: • CP-even = short lived • CP-odd = long lived • /=0.120.06 • New physics can only(?) decrease  Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  44. Bs mixing I – Lifetime difference • BS J/y fm+m- K+K- • BVV decays: Heavy and Light state decay with distinct angular distributions and different lifetimes. • CDF (260 pb-1) • 1/4 heavy - 3/4 light state • Lifetime - theavy ~ 2 x tlight D0 (450pb-1) Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  45. Top Production at the Tevatron • Pair production • spair- theory = 6.7 pb. ~ 85% ~ 15% g g All of these theoretical values assume a top quark mass of 175 GeV/c2 at a center of mass energy of 1.96 TeV. s channel • Single top • Not yet observed • ss-channel - theory = 0.88 pb. • st-channel - theory = 1.98 pb. t channel Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  46. Test of Standard Model Impact of CDF+D0 Top Quark Mass = 172.7 ± 2.9 GeV future CDF+D0 (4 fb-1) Good agreement between direct measurements and indirect SM prediction <219 GeV with LEP Excluded Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  47. Heavy states decaying to ttbar D0 370pb-1 l+jets CDF 320 pb-1 l+jets Both experiments exclude Xttbar Br larger than few pb-1. Leptophobic Z' in topcolor models with (Z')=0.012m(Z') are excluded for up to Z' masses of about 700 GeV Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

  48. sbottom and stop searches • to be completed Rolf Oldeman (University of Liverpool) Flavour studies and BSM searches at the Tevatron

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