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TeVatron Highlights

TeVatron Highlights. Jean-Fran ç ois Grivaz (LAL-Orsay) for the CDF and D Ø Collaborations. Disclaimer. Looking at the agenda, the main emphasis of this workshop appears to be on physics beyond the standard model . The selection of topics for this talk has been made accordingly,

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TeVatron Highlights

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  1. TeVatron Highlights Jean-François Grivaz (LAL-Orsay) for the CDF and DØ Collaborations FRIF - November 13, 2006

  2. Disclaimer Looking at the agenda, the main emphasis of this workshop appears to be onphysics beyond the standard model. The selection of topics for this talk has been made accordingly, rather than aiming at completeness. Also, the machine and detector aspects have been covered earlier this morning, and will not be repeated here. FRIF - November 13, 2006

  3. Chicago  Booster CDF DØ Tevatron p source Main Injector p-pbar collisions at 1.96 TeV c.o.m. energy Peak luminosity: 2.4 E32 cm-2s-1 Delivered: > 2 fb-1 In this talk: up to 1.2 fb-1 At the TeVatron: Still the energy frontier For details, see: CDF: http://www-cdf.fnal.gov/physics/physics.html DØ: http://www-d0.fnal.gov/Run2Physics/WWW/results.htm Unless there are good reasons, I’ll pick examples in either one. FRIF - November 13, 2006

  4. Tools for beginners Electron: an electromagnetic cluster linked to a track Muon: a track linked to hits in the muon system Tau: a low track multiplicity narrow jet Photon: a trackless electron Neutrino: missing transverse energy from the full calorimeter Jet: constructed from calorimeter clusters with a cone algorithm b-jet: a jet associated with tracks forming a secondary vertex (or with large impact parameters) FRIF - November 13, 2006

  5. A bit ofStandard Model Physics FRIF - November 13, 2006

  6. Inclusive jet production Systematic uncertainties from the Jet Energy Scale Now non-zero impact on PDFs Agreement with NLO QCD (Can be used to constrain e.g. compositeness models) FRIF - November 13, 2006

  7. CDF preliminary (1.1 fb-1) Z Rapidity dZ/dyZ(pb) Z Rapidity DØ Prelim. (230 pb-1) W Charge Asymmetry Lepton Rapidity Some recent electroweak results DØ prelim. (230 pb1) W Charge Asymmetry Observation of WZ production (3l final state) Constraining the PDFs FRIF - November 13, 2006

  8. The top quark Top decay: Wb (100% in SM) Pair production (6.7 pb) 85% (15% ggtt)  top mass, charge, spin, decay modes [decays before hadronizing] Single production (3 pb) Vtb [t(Wl)b]+b Stuck between Wbb and tt backgrounds 2.3 Has it been observed ? FRIF - November 13, 2006

  9. Top mass measurement t1(We/)b t2(Wqq’)b 1 lepton + missing ET + 2 light jets + 2 b jets Complications:additional jets (ISR/FSR), missing pz of neutrino, jet combinatorics Systematic uncertainties: The largest one is the jet energy scale. It is constrained “in situ” by the W mass, hence becoming a statistical uncertainty. • Methods: • Template: • (determine with MC simulation which • top mass fits best the distribution of • reconstructed top mass in the data) • Matrix Element: • (Inject the full kinematic information • into a likelihood fit to the LO ME • using parton to jet transfer functions) • Most powerful method • CDF single best with 940 pb1 (2.6 GeV total uncertainty) CombiningCDF&DØ (and also with dileptons and all-jets) mtop = 171.4  2.1 GeV FRIF - November 13, 2006

  10. The Bs system (SM 0.3o) BsH/L mostly CP-odd/even ms measurement: In real life: (1Dcosmt) Technically: fit A in (1ADcosmt) Find m for which A=1 Statistics Decay length and Momentum resolutions Flavor tagging Efficiency and Purity FRIF - November 13, 2006

  11. Pictorially: Combine all taggers (Neural Network) Calibrate on B+/0 decays (+ Monte Carlo for same side tagging) Use both semileptonic and hadronic decays Larger statistics in semileptonic decays But much better resolution for hadronic decays FRIF - November 13, 2006

  12. A   observation: CDF 1 fb1 (in agreement with SM expectation) FRIF - November 13, 2006

  13. s measurements From time dependent analysis of decay angular distributions In addition: Flavor specific lifetime in (BsDs) (50% even-odd) BsK+K lifetime (mostly CP-even) BsDs(*)+Ds(*) BR (“”) s is 2.3 away from 0 and in agreement with SM (s0 would reduce it) FRIF - November 13, 2006

  14. Searches for new particlesandnew phenomena FRIF - November 13, 2006

  15. Extra Gauge Bosons e.g. Z’ within E(6) GUTs e.g., W’ in L-R models M(Z’-seq.) > 850 GeV MT = M(electron-pT,missing-ET) (somewhat lower limits in) (canonical E(6) models) M(W’-seq.) > 965 GeV FRIF - November 13, 2006

  16. Leptoquarks LQ lq (BR = ) or LQ q (BR = 1 – ) Pair produced  llqq, lqq or qq final states Search in the qq channel Topology = Acoplanar jets + Missing ET Large backgrounds from QCD multijets (at low Missing ET) and from SM processes (Z  jets) 86 events vs 75.215.2 expected (after Missing ET 80 GeV) FRIF - November 13, 2006

  17. 1st generation Leptoquarks Searches in the eeqq and eqq channels 2 electrons, 2 jets and Z-veto 1 electron, missing ET and W-veto ST = ET(e1)+MET+ET(j1)+ET(j2) ST = ET(e1)+ET(e2)+ET(j1)+ET(j2) (After all other cuts) 1 event vs0.5  0.1 expected 1 event vs3.6  1.2 expected For 2nd generation, similar searches with e   FRIF - November 13, 2006

  18. 1st and 2nd generation Leptoquarks M1  256 GeV( = 1) M1  234 GeV ( = 0.5) M1 > 136 GeV ( = 0) (DØ – Run I + Run II) M2  224 GeV( = 1) M2  208 GeV ( = 0.5) M2 > 117 GeV ( = 0) (CDF – Run II) FRIF - November 13, 2006

  19. 3rd generation Leptoquarks The bb channel The bb channel Wait for SUSY… Sbottom search Stop search with RPV FRIF - November 13, 2006

  20. SUperSYmmetry For such an audience, no “What is SUSY ?”, or “Why SUSY ?” Which SUSY ? More or less constrained MSSM, à la mSUGRA neutralino-LSP with or without R-parity violation Gauge Mediated SUSY Breaking gravitino-LSP and neutralino-NLSP Anomaly Mediated SUSY Breaking wino-LSP and long-lived chargino Split SUSY long-lived gluino FRIF - November 13, 2006

  21. (m)SUGRA m0 m1/2 tan() A0 sign() Two main search streams at the Tevatron: • Squarks and gluinos multijets + missing ET • large production cross sections • large experimental backgrounds • Electroweak gauginos with leptonic decays (Trileptons) • low production cross sections • typically low leptonic branching ratios • clean experimental signature FRIF - November 13, 2006

  22. Trileptons • Arise from chargino-neutralino • associated production • “Golden” SUSY signature but: • - low cross sections ( BR) • - soft leptons • - taus (at large tan) • Needs large integrated luminosity • Combine various final states (Also decays via W/Z exchange) • General strategy(similar in CDF and DØ): • Two isolated (rather soft) e or  • Require some Missing ET () •  channel-dependent cuts (e.g. anti Z, ) • An isolated third lepton or track (sensitive to ’s), or • Two same sign leptons • Main backgrounds: DY, WW, WZ, W (+ a bit of bb and mis-ID) FRIF - November 13, 2006

  23. Some control plots… FRIF - November 13, 2006

  24. …and in the end… Missing ET in +e/ Missing ET pT(3) in ee+track The results of the various channels are combined, “weighted” according to their sensitivity, with overlaps taken into account. Cross-section upper limits & mass lower limits within specific models. FRIF - November 13, 2006

  25. Models = “favorably tweaked” mSUGRA Both CDF and DØ setms = mse = ms m0 = 60 GeV  2-body decays enhanced () s mixing on ( sL component)  decays to ’s enhanced () • m(sl) = m(20) +  • only 3-body decays () • s mixing off (no sL component) •  decays to ’s = to e/ () Some work ahead for the TEV-WG… FRIF - November 13, 2006

  26. Generic squarks and gluinos • Strong production ( Large cross sections ) of: • sq-sqbar and sq-sq  at least 2 jets + missing ET (sq  q) • gl-gl  at least 4 jets + missing ET (gl  qq) • sq-gl  at least 3 jets • Cascade decays complicate the picture  model needed (mSUGRA) • Main backgrounds: • Instrumental (QCD multijets with fake missing ET) • (W(missed lepton)+) +jets (also from ttbar) • (Z  ) +jets (irreducible) DØthree analyses optimized for each of these processes reduces QCD to a negligible level CDF3-jet analysis optimized mostly for m(sq)  m(gl) larger QCD background, estimated from control regions FRIF - November 13, 2006

  27. Main analysis cuts: • Data cleaning • Jet1,2(,3(,4)) pT • Missing ET • HT = sum of jets pT’s • Lepton veto • Angles (jet,missing ET) HT225 GeV (m(gl)=240 GeV) FRIF - November 13, 2006

  28. You have seen or will see other versions of this plot. • CDF vs DØ differences: • 371 vs 310 pb-1 • tan = 5 vs 3 (little impact) • 4 vs. 5 flavors (little impact) • Theoretical uncertainty on • the signal cross section: • CDF includes it as a systematic • uncertainty in the computation • of the cross section limit • DØ reduces instead the theoretical • cross section by its uncertainty • (more conservative): yellow band • …and CDF was a bit “lucky”. Some work ahead for the TEV-WG… Mgl > 387 GeV (when Mgl~Msq) Mgl > 241 GeV & Msq > 325 GeV FRIF - November 13, 2006

  29. stR Stop A light stop can be expected: top-Yukawa impact in RGE First scenario: stop NLSP and  LSP with stc (FCNC) (relevant as long as m(st) < m(b)+m(W)+m()) (in SUGRA, needs M1 < M2 at GUT scale) + Large L-R mixing •  1 c-jet (soft tag) + missing ET (optimized for various m(st),m()) Main backgrounds: W/Z+jets FRIF - November 13, 2006

  30. Stop Second scenario: • Light sneutrino  st  b l s • 2 leptons (+b-jets) + missing ET (s) (optimized for various m(st),m(s)) e and  final states analyzed Main backgrounds: Z at low mass, top at high mass e analysis: ST=pT(e)+pT()+missing ET with two signal examples Stop exclusion up to m(top) FRIF - November 13, 2006

  31. m(sb) = 140 GeV m() = 80 GeV Sbottom A light sbottom can be expected at large tan. Search for sbottom pair production, with sbb   1 b-jet + missing ET(optimized for various m(sb),m()) CDF also searched for sbottom from decays of pair-produced gluinos: gluino b sb (100%)  3/4 b-jets + missing ET With 156 pb-1,sbottom masses up to 240 GeV are excluded IF m(gluino) < 280 GeV (and m() = 60 GeV) FRIF - November 13, 2006

  32.  l121 ~ ~  e  0 1 e- R-parity violation Possible additional terms in the superpotential: With a  term, only RPC pair production, mostly + and 20, with (cascade) decays to LSP’s followed by RPV decays e.g.  4 charged leptons + missing-ET With a ’i11term, also resonant production: e.g. FRIF - November 13, 2006

  33. R-parity violation: ijk DØ: 121, 122, 133 considered Three trilepton searches combined: eee/ 0.90.4 (background /e 0.40.1 (events 0 candidate ee 1.31.8 (expected CDF also used clean four-lepton topologies: 0 candidate vs 0.0080.004 bg. expected ! For 133, ee most powerful at large tan and low m0: m(10) > 115 GeV for tan = 20, A0 = 0,   0 and m0 = 100 GeV NN -ID validated with Z FRIF - November 13, 2006

  34. R-parity violation: ’ijk DØ: ’211resonant production CDF: ’333pair production Look for (e/)(hadrons) +2 jets Reconstruct: m(smuon) = m(jj) m(10) = m(jj) 2 candidates vs. 2.30.5 bg. No accumulation m(smuon) > 210 to 363 GeV for ’211 > 0.04 to 0.10 (tan=5, A0=0 and  < 0) (Also LQ3) FRIF - November 13, 2006

  35. Neutral Long Lived Particles DØsearch motivated by 3 dimuon events in the NuTeV experiment Production and decay model: SUSY RPV with a small 122 Look for displaced dimuon vertices (5 to 20 cm) Calibrate with Ks decays (383 pb-1) 0 candidate vs. 0.81.6 bg. Convert NuTeV (p-p at 38 GeV) to DØ (p-pbar at 1.96 TeV) FRIF - November 13, 2006

  36. Charged Massive Stable Particles Long-lived charginos are expected in some AMSB models with a “wino-LSP” (small  – 10 mass difference) They would appear in DØ as slowly-moving muons  Make use of the time information of the muon system scintillators For a 150 GeV chargino: 0 candidates for 0.690.05 bg. FRIF - November 13, 2006

  37. Gauge Mediated SUSY Breaking In GMSB, the LSP is a light gravitino G A 10 NLSP decays into +G • Inclusive search for  + missing ET pT() > 25 GeV Missing ET > 45 GeV All backgrounds determined from data (fake photons from dijet events, We+/jet) “mGMSB Snowmass slope” (N=1, Mm = 2,   0, tan = 15) Signal dominated by 20production m(10) > 120 GeV 4 candidates vs. 1.80.7 bg. FRIF - November 13, 2006

  38. m(10 ) = 50, 90, 200 GeV Stopped Gluinos In “Split-SUSY”, squarks are ultra-heavy  long-lived gluinos Such gluinos form R-hadrons which may stop in the DØ calorimeter. (A. Arvanitaki et al., arXiv:hep-ph/0506242) After a while, they decay into a gluon + 10 (q-qbar-10 is also possible). Strategy: look for a randomly oriented monojet in an otherwise empty event (diffractive trigger). Backgrounds: beam and cosmic muons, measured in data. Excludes gluino masses up to 300 GeV FRIF - November 13, 2006

  39. Indirect limits from Bs SM:Bsmm is heavily suppressed SUSY: largeenhancement CDF search: • Huge dimuon background • Discriminate using • Decay length • Isolation • Pointing • Normalize to B+J/ K+  GeV 2 GeV Carena 1 candidate event selected in a 60 MeV mass window vs. 1.40.4 bg. expected BR(Bs) < 1. 10-7 Limit at 95% C.L (780 pb-1): FRIF - November 13, 2006

  40. Extra-dimensions …come in many flavors: LED, TeV-1, UED, RS • Two classes of models considered: • ADD • 2 to 7 large (sub mm) EDs • gravity propagates • freely in the bulk • KK excitations • cannot be resolved • RS • one 5th (infinite) ED • with warped geometry • gravity is localized • on a brane other than the SM • KK excitations • have spacings of order TeV FRIF - November 13, 2006

  41. g g g q GKK GKK g q f f V GKK GKK f f V Large Extra Dimensions Two main search streams at the TeVatron: Real graviton emission Apparent energy-momentum non-conservation in 3D-space  “Monojets” Direct sensitivity to the fundamental Planck scale MD Virtual graviton exchange Modifies SM cross sections Sensitivity to the theory cutoff MS (MS expected to be  MD) FRIF - November 13, 2006

  42. Monojets CDF search in 1.1 fb-1: • Main selection cuts: • one high pT jet ( 150 GeV) • (soft jets from ISR are allowed) • isolated lepton veto • Missing ET away from jets • Missing ET  120 GeV Main background: (Z ) +jet Calibrated with (Zll and Wl) + jet QCD is negligible 779 events selected 819  71 expected FRIF - November 13, 2006

  43. High pT dileptons & diphotons DØ search in 200 pb-1 combines ee and  to maximize the sensitivity Fit of Data to SM+QCD+LED(MS) Still world tightest limits: MS > 1.36 TeV MS >1.43 TeV w/DØ@Run I in the GRW formalism FRIF - November 13, 2006

  44. Randall – Sundrum gravitons Here too, most of the sensitivity is in diphotons (BR = 2ee) Two model parameters: Mass and coupling (/MPl) For /MPl = 0.1: M  870 GeV FRIF - November 13, 2006

  45. Having found nothing yet…Look for the unexpected Signature based searches CDF:  + X in 0.7 to 1 fb-1 X=e 2 vs. 4.50.8 X= 0 vs. 0.50.1 X= 4 vs. 1.90.6 l  + Missing ET in 0.3 fb-1 l=e 25 vs. 19.83.2 l= 18 vs. 15.32.2 (CDF Run I excess not confirmed) (Also multileptons + photon) FRIF - November 13, 2006

  46. SM Higgs boson searches LEP/TeVatron indirect: MH < 166 GeV LEP direct: MH > 114 GeV Hint at 115 GeV MH < 135 GeV: Hbb gg H bb hopeless gg H  OK for SUSY @ large tan H(W  l) and H(Z  ll/): best processes Hbb OK for SUSY @ large tan Htt maybe (under study) MH >135 GeV: H WW* gg H (W  l)(W* l): best process Also (H WW*)(W l / Z ll) FRIF - November 13, 2006

  47. High mass: HWW Search in the ee, e and  + Missing ET final states The WW background is reduced using the spin correlations: smaller ll angle in the Higgs signal 10 ee events vs 10.30.6 expected 18 e events vs 24.41.5 expected 9  events vs 9.8  0.8 expected FRIF - November 13, 2006

  48. Low mass: (Wl)(Hbb) e/ + Missing ET + 2jets ( 1 b-tag) 2 tags 2 tags control of the Wbb and top backgrounds (shape and normalization) dijet mass resolution Main challenges: FRIF - November 13, 2006

  49. Low mass: (Z)(Hbb) Missing ET + 2jets ( 1 b-tag) + 0 lepton Control regions: QCD = MET close to a jet – EWK =  1 lepton control of the QCD background (shape and normalization) dijet mass resolution Main challenges: (This search is also sensitive to WH with “missed” lepton) FRIF - November 13, 2006

  50. Combination Combine 16 channels…: [W(e/)](Hbb 1 and 2-tags) [Zee/] (Hbb 1 and 2-tags) [Z)] (Hbb 1 and 2-tags) [W(e/)][HW{W (e/)}] [HWW (e/)(e/)] Combine two experiments (equivalent to one with 1.3 fb1) 95% CL limit / SM cross section With realistic improvements, 95%CL = SM with 3 fb1 @ 115 GeV 5 fb1 @ 160 GeV 8 fb1 from 115 to 185 GeV FRIF - November 13, 2006

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