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Search For New Physics at the TeVatron

Search For New Physics at the TeVatron. Jean-Fran ç ois Grivaz LAL-Orsay. http://www-cdf.fnal.gov/physics/exotic/exotic.html http://www-d0.fnal.gov/Run2Physics/WWW/results.htm. Chicago . CDF. DØ. Tevatron. p sou rce. Main Injector & Recycler. The Tevatron at Run II.

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Search For New Physics at the TeVatron

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  1. Search For New Physics at the TeVatron Jean-François Grivaz LAL-Orsay http://www-cdf.fnal.gov/physics/exotic/exotic.html http://www-d0.fnal.gov/Run2Physics/WWW/results.htm Euro-GDR 25-November-2004

  2. Chicago  CDF DØ Tevatron p source Main Injector & Recycler The Tevatron at Run II • New Main Injector • + Recycler • Higher energy • (1.96 TeV vs 1.8 TeV) • => Higher cross sections • (~30% for the top) • Higher antiprotonintensity • 6x6  36x36 bunches • (3.5 s  396 ns) • antiproton “recycler” • => Higher luminosity Euro-GDR 25-November-2004

  3. Luminosity performance In 2004: • Peak luminosity: • 4 - 8 1031 cm-2 s-1 • Weekly delivered: • 8 - 16 pb-1 • Data taking efficiency: • 80 - 90% • Physics quality data: • up to 350 pb-1 • analyzed as of ICHEP04 1032 Euro-GDR 25-November-2004

  4. Searches for New Phenomena Supersymmetry: (m)SUGRA, GMSB Extra Dimensions: large, warped Extended Gauge Theories: Z’ Higgs bosons: SUSY, SM In back-up slides: RPV, leptoquarks, excited leptons, doubly-charged Higgses Not covered : TeV–1 ED, Technicolor, Little Higgs but same signatures as e.g., LED, SM-Higgs, RS-gravitons Real exotics (e.g.monopoles) Euro-GDR 25-November-2004

  5. Supersymmetry Euro-GDR 25-November-2004

  6. (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 Euro-GDR 25-November-2004

  7. Trileptons (I) • 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) DØ analysis based on 147  249 pb1 Combines eel, el, l and same sign dimuon final states Addresses “just beyond LEP”mSUGRAwith low mass sleptons Euro-GDR 25-November-2004

  8. Trileptons (II) • Two isolated (rather soft) e or  • Require some Missing ET •  channel-dependent cuts (e.g. anti Z) • Two same sign muons, or • An isolated third track (no e or  ID) • Main backgrounds: WW, WZ, W, a bit of bb • Altogether: 3 events observed vs 2.9  0.8 expected Euro-GDR 25-November-2004

  9. Trileptons (III) Substantial improvement wrt Run I: m()  97 GeV for m(slepton) m() Should soon probe virgin mSUGRA territory Euro-GDR 25-November-2004

  10. Stop and sbottom • CDF has searched for charged massive particles in 53 pb1 • appear as slow moving (TOF) high pT muons • result interpreted for (meta)stable stop •  m(stop) 108 GeV (isolated) or 95 GeV (non-isolated) • CDF has searched for sbottoms • in gluino decays (156 pb1) • assumes sb1 much lighter than • all other squarks (large tan) • gluino  sb1 b •  4 b-jets + Missing ET • for gluino pairs • the selection requires at least • one b-tag, no isolated lepton • With 2 b-tags: 4 vs 2.6  0.7 expected Euro-GDR 25-November-2004

  11. Generic squarks (I) • Strong production of: • sq-sqbar • sq-sq • sq-gl • gl-gl In 85 pb1, DØ has searched along the “minimum sq-mass line” of mSUGRA: very low m0 (25 GeV), (tan = 3, A0 = 0,   0), scan over m1/2  Mostly sq-sqbar with sq  q   Acoplanar jets + Missing ET Euro-GDR 25-November-2004

  12. QCD Generic squarks (II) • Main selection cuts: • at least two high pT jets • isolated lepton veto • Missing ET should not be • along or opposite to a jet • Sum of jet pT 275 GeV • Missing ET  175 GeV • Main backgrounds left: • (Z  ) + jets • (W ) + jets • QCD negligible 4 events selected vs 2.7 +2.3/1.5 expected Euro-GDR 25-November-2004

  13. Generic squarks (III) Slight improvement over CDF-Run I along that “minimum sq-mass line”: (msq 292 GeV and mgl 333 GeV) How relevant are the Tevatron results on squarks and gluinos ? LEP slepton and chargino limits  much tighter constraints on m0 and m1/2 within mSUGRA (or even MSSM with unification) The Tevatron should consider models with smaller M3/M2 ratios: not unnatural in GUTs (e.g. M3/M2 ~ 1 if SUSY breaking by a 75) or in some string inspired models Euro-GDR 25-November-2004

  14. GMSB with  NLSP (I) Remember the CDF ee + Missing ET event ?…  + gravitino Inclusive search for   Missing ET by both CDF / DØ • Photon = electron without track • Photon ET  13 / 20 GeV • Missing ET > 45 / 40 GeV • Mild topological cuts • Main backgrounds: • EM-jets (or real QCD photons) • + fake Missing ET • electron + photon • + real Missing ET • All determined from the data CDF : 0 vs 0.3  0.1 expected DØ : 2 vs 3.7  0.6 expected Euro-GDR 25-November-2004

  15. GMSB with  NLSP (II) • Interpretation within mGMSB • with: • N = 1 • Mmessenger = 2, •   0, • tan = 15 (aka “Snowmass slope”) • Signal dominated by • chargino-neutralino production 263 pb-1 World best limit: m  108 GeV (DØ) (Also 93 GeV (CDF)) Euro-GDR 25-November-2004

  16. “Superjets” ? CDF @ Run I observed an excess of W + 2/3 jet events with  1 jet “double-tagged” (Secondary vertex + Soft lepton) 13 vs 4.4  0.6 expected An interpretation in terms of light sbottom + RPV () has been suggested (not by CDF) DØ has searched for such an anomaly in 150 pb-1 of Run II data and did not find any. Let’s wait and see what CDF will find… Euro-GDR 25-November-2004

  17. Bs  In SM, tiny BR ~ 3.5 109 (and 25 times smaller for Bd) But in SUSY, a (tan)6 factor could lead to an enhancement by as much as three orders of magnitude Select dimuons originating from displaced vertices, and look inside a mass window: BR limits (95% CL): 5.0 10-7 (DØ 240pb-1) and 7.5 10-7 (CDF 171 pb-1) Close to getting relevant Euro-GDR 25-November-2004

  18. Extra Dimensions Euro-GDR 25-November-2004

  19. Models of Extra Dimensions • 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 Euro-GDR 25-November-2004

  20. 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) Euro-GDR 25-November-2004

  21. Monojets DØ search in 85 pb-1: • Main selection cuts: • one high pT jet ( 150 GeV) • (soft jets from ISR are allowed) • isolated lepton veto • Missing ET away from all jets • Missing ET  150 GeV QCD Main background: (Z ) +jet QCD is negligible 63 events selected 100 +51/-32 expected Large error from Jet Energy Scale (Updated result coming soon) Euro-GDR 25-November-2004

  22. 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) World tightest limits: MS > 1.36 TeV MS >1.43 TeV w/DØ@Run I in the GRW formalism Also 1.1 TeV: from CDF in dielectrons with 200 pb-1 from DØ in dimuons with 250 pb-1 Euro-GDR 25-November-2004

  23. Randall – Sundrum gravitons Here too, most of the sensitivity is in diphotons (BR = 2ee) DØ uses the same ee + data set as for the LED search 300 GeV RS-graviton DØ Run II Preliminary Two model parameters: Mass and coupling (/MPl) For /MPl = 0.1: M  785 GeV Also 690 GeV from CDF in diphotons with 345 pb-1 Euro-GDR 25-November-2004

  24. Z’ Euro-GDR 25-November-2004

  25. DØ Run II Preliminary 600 GeV Z’ Z’ in dielectrons Now select only electron pairs (much reduced QCD background) For an SM-like Z’: M  780 GeV Limits for SM-like Z’ and various E6 models Also M > 750 GeV from CDF (200 pb-1) Euro-GDR 25-November-2004

  26. Z’ in dimuons Dimuons vs. dielectrons: lower background but worse resolution Z’ limits in various E6 models For anSM-like Z’: M  735 GeV Also M 680 GeV from DØ (250 pb–1) Combining ee and : M (SM-like Z’)  815 GeV(CDF) Euro-GDR 25-November-2004

  27. Z’ in  CDF in 195 pb-1 4 events (eh,h,hh) vs 2.8  0.5 expected Euro-GDR 25-November-2004

  28. Higgs bosons Euro-GDR 25-November-2004

  29. SUSY-Higgs @ large tan Hbb coupling enhanced DØsearch for  3b jets (130 pb-1) Euro-GDR 25-November-2004

  30. SM Higgs boson searches LEP indirect: MH < 260 GeV LEP direct: MH > 114 GeV Hint at 115 GeV MH < 130 GeV: Hbb gg H bb hopeless (H  maybe) H(W  l) and H(Z  ll/): best processes Hbb OK for SUSY @ large tan Htt maybe MH >150 GeV: H WW* gg H (W  l)(W* l): best process Also (H WW*)(W l / Z ll) Euro-GDR 25-November-2004

  31. (147 – 177 pb–1) (200 pb–1) High mass: HWW DØsearch 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 2 ee events vs 2.7 0.4 expected 2 e events vs 3.1  0.3 expected 5  events vs 5.3 0.6 expected Euro-GDR 25-November-2004

  32. Low mass: (Wl)(Hbb) CDF search in 162 pb–1: e/ + Missing ET + 2jets ( 1 b-tag) Similar DØ search (174 pb–1 - e only) with 2 b-tags Still a long way to go… Euro-GDR 25-November-2004

  33. Now LHC Are we going there ? Updated signal and background cross sections Full detector simulation + established analysis techniques + “reasonable extrapolations” + Signal shape (vs. mass window) (but no systematics…) If we are lucky: 3s evidence If not…: 95% CL exclusion of the MSSM range Euro-GDR 25-November-2004

  34. Final remarks The Higgs is not the whole story… With a data sample at least 20 to 40 times larger than at Run I, collected at higher energy with improved detectors, there is a lot of beautiful (but difficult) physics to be done: • W and top masses, top properties, single top production • B physics: Bs mixing, rare Bs decays, Bs and Lb lifetimes • Exploration of new territory (SUSY, LED…):we may be lucky… • already well underway • interaction with theorists welcome ! With a steadily improving collider performance there are still a number of years and fb–1 ahead of us for frontier physics at the Tevatron. Euro-GDR 25-November-2004

  35. Back-up Slides Euro-GDR 25-November-2004

  36. The CDF and DØ upgrades • New tracking: silicon and • fibers in 2T magnetic field • Upgraded muon system • New DAQ and new trigger • (commissioning displaced track) • New silicon and drift chamber • Upgraded calorimeter (plug) • and muon system • New DAQ and new trigger, • (displaced track trigger) … and new software (C++, OO) Euro-GDR 25-November-2004

  37. CDF/D0 2 fb-1goal! The Run II Menu With 2 fb-1: • Top mass to  3 GeV • W mass to  30 MeV • Bs mixing to 20 ps-1 • Exclude mH = 115 GeV • And much more… • High pT jets • LED to 2 TeV • SUSY And beyond: Euro-GDR 25-November-2004

  38. RPV with ijkLiLjLk coupling (I) DØ has searched for multilpeton final states arising from SUSY particle pair production with R-parity violating decays of two neutralino LSP’s in the regime where  is small enough so that only the LSP has an RPV decay, and large enough for its lifetime to be negligible. The couplings considered were 121  eeee, eee or ee +  122  , e or ee +  Three isolated (rather soft) e or  Require some Missing ET  channel-dependent cuts (e.g. anti Z) Euro-GDR 25-November-2004

  39. RPV with ijkLiLjLk coupling (II) 121: 0 vs 0.5  0.4 expected (238 pb-1) 122: 2 vs 0.6  1.9 expected (163 pb-1) eee/ A search has also been performed for the 133coupling, in the eeX final state, with   hadrons +  (199 pb-1) Resonant single slepton or sneutrino production via a 211 RPV coupling has also been investigated (154 pb-1) m 200 GeV Euro-GDR 25-November-2004

  40. M  241 GeV Leptoquarks LQ lq (BR = ) or LQ q (BR = 1 – ) Pair produced  llqq, lqq or qq final states 2nd generation LQ in qq (CDF – 200 pb-1): 2 muons, 2 jets, Z-veto 2 events vs3.2  1.2 expected Euro-GDR 25-November-2004

  41. 1st generation Leptoquarks (I) DØanalysis performed in the eeqq and eqq channels (175 pb-1) 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) (Before W-veto) (After all other cuts) 0 events vs0.4  0.1 expected 2 events vs4.7  0.9 expected Euro-GDR 25-November-2004

  42. 1st generation Leptoquarks (II) M  238 GeV( = 1) M  213 GeV( = 0.5) (DØ – 175 pb-1) Also CDF with 200 pb-1: M  230 GeV( = 1) M  176 GeV( = 0.5 not combined) Euro-GDR 25-November-2004

  43. Leptoquarks in the qq channel Topology = Acoplanar jets + Missing ET Large backgrounds from QCD multijets and from SM processes (Z  jets) Also DØ with 85 pb-1: M  109 GeV 124 events vs 118.5 14.5 expected Euro-GDR 25-November-2004

  44. Excited electrons CDF search in the ee final state (200 pb-1) Z - veto 3 events vs 3.0  0.4 expected (main background = Z) Euro-GDR 25-November-2004

  45. Doubly-charged Higgs Bosons Doubly charged Higgs (from Higgs triplets) are predicted in, e.g., LR-symmetric models CDF has searched for H pair production in 240 pb-1 The signature is a pair of same sign ee, e or  0 ee events vs 1.5 +0.90.6 expected 0 e events vs 0.4 0.2 expected 0  events vs 0.8 +0.50.4 expected Also DØ in  (113 pb-1): M(HL) > 118 GeV M(HR) > 98 GeV Euro-GDR 25-November-2004

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