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Latest New Phenomena Results from

1. Latest New Phenomena Results from. ITEP, Moscow 26.11.2007. For the DO Collaboration. Alexey Popov (IHEP, Protvino). 2. New Phenomena with. Supersymmetry:. Squarks/Gluinos Charginos/Neutrallinos. Leptoquarks (2 generation) RS Gravitons Extra Gauge Bozons ( )

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Latest New Phenomena Results from

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  1. 1 Latest New Phenomena Results from ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  2. 2 New Phenomena with • Supersymmetry: • Squarks/Gluinos • Charginos/Neutrallinos • Leptoquarks (2 generation) • RS Gravitons • Extra Gauge Bozons ( ) • Excited Fermions ( ) • Long-lived Particles Results from statistics ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  3. 3 Data Set “Run IIa” ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  4. 4 Supersymmetry • Most studied extension of the Standard Model to solve many of its shortcomings • New (s)particles, differing from their SM partners by spin 1/2 R-parity: MSSM: R-parity conservation - LSP is stable, s-partners are created in pairs • SUSY must be broken: mSUGRA, GMSB etc. • mSUGRA parameters: ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  5. 5 Supersymmetry: squarks and gluinos • MSSM (mSUGRA) • R-parity conserved (LSP stable) “di-jet” Low , (at least 2 jets) “3-jet” Medium , (at least 3 jets) “gluino” High , (at least 4 jets) ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  6. 6 Squarks and gluinos: results mSUGRA parameters ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  7. 7 Squarks and gluinos: results Using minimal cross-section ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  8. 8 Squarks and gluinos: results CDF ( ): Iso-squark/gluino mass Yellow band: variations due to PDF uncertainties and renormalization/factorization scale variations ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  9. 9 Charginos and Neutrallinos: 3l - state • Gaugino pair production via EW interactions • Small cross-sections (0.1 – 0.5 pb) • R-parity conservation LSP stable • LSP escapes detection large MET • SUSY signature: Small cross-sections but very clean signature • Two electrons or muons • Third lepton • Large MET ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  10. 10 Charginos and Neutrallinos: 3l - state ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  11. Charginos and Neutrallinos: 3l - state 11 ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  12. 12 Charginos and Neutrallinos: Like-sign mm Very soft third lepton possible. Instead of requiring 2l+track require 2l of same charge: low background ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  13. 13 Charginos and Neutrallinos: Like-sign mm ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  14. 14 Trilepton results “Heavy squarks”: maximal production cross-section “3l-max”: mSUGRA with light sleptons, large BR(3l) “large-m0”: W/Z exchange dominates, small BR(3l) in “3l-max” scenario ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  15. 15 Search for GMSB in diphoton final states Gauge Mediated SUSY Breaking • achieved by the introduction of the new chiral • supermultiplets (messengers) which couple to the source • of SUSY breaking • LSP is gravitino, NLSP (neutrallino or slepton) • decays to LSP and photon, LSP escapes detection • Signature: gg + MET One dimensioned parameter L – effective energy scale of SUSY breaking. ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  16. 16 Leptoquarks • Leptoquark – boson with third-integer charge, carrying lepton and quark quantum numbers (GUT, Technicolor, Compositeness) • Three generation, each coupling to one fermion generation only • Pair production: no dependence from LQ coupling to l and q Maximal ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  17. 17 Leptoquarks: Second Generation M(LQ) > 214 GeV (b=0.5) CDF Run II ( ) M(LQ) > 170 GeV (for mn+jets) M(LQ)>208 GeV (mm,mn,nn combined) ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  18. 18 Randall-Sundrum Gravitons RS Model • Use Extra Dimensions (ED) to address a hierarchy problem • One 5th (infinite) ED with warped geometry • Gravity is localized on a Plank brane (other than SM brane) • Gravitons appear as a KK excitations in SM brane Signature: narrow, high-mass resonances decaying to ll or gg Two parameters: – mass of the first excited mode of the G – dimensionless coupling to the SM fields ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  19. 19 Randall-Sundrum Gravitons (combined) CDF ( ): ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  20. 20 New Gauge Bosons Predicted in several beyond SM scenarios (GUT, left-right symmetric models, etc.) (SM-like W) CDF (Run II, en) ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  21. 21 New Gauge Bosons Previous DO Run II results: (SM-like couplings to fermions) CDF Run II ( ) Small excess of data in ee channel at 240 – 250 GeV ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  22. 22 Lepton compositeness • Quarks and leptons may be made of smaller “pieces” (preons) • This allows excited states ( ) • Contact Interaction (CI) and Gauge Interactions • – compositeness scale parameter Expected signal for Data: SM expectations: events events ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  23. 23 Lepton compositeness CDF Run II ( ): DO Run II ( ): CDF Run II ( ): ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  24. 24 Long-lived particles decaying into Z • Predicted in many “beyond the SM” models (GMSB SUSY, hidden valley models, models with extended Higgs sector, fourth generation quarks ( ), e t c.) • Fourth generation quarks model was chosen as a benchmark, events with at least one Z decaying to state were selected ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  25. 25 Long-lived particles decaying into Z Benchmark: No excess of events at a large distance from the beam Calculated limits (mass vs. ct plot) ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  26. 26 Conclusion • Many searches for beyond Standard Model effects are progressing at Tevatron, you can find much more results on the WWW DO NP page: http://www-d0.fnal.gov/Run2Physics/WWW/results/np.htm CDF “Exotic” page: http://www-cdf.fnal.gov/physics/exotic/exotic.html • Standard Model works pretty well and no significant deviations so far have been observed at DO and CDF • All search analysis are benefiting from more data and we expect with in Run II to increase data set by a factor of ~5 – 10 • Discoveries may come later – stay tuned! ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  27. Backup slides

  28. B1 Squarks: t + jets + MET • In some mSUGRA parameters region (lightest SUSY partner of t) might be the lightest of all sleptons • Enhanced BR to t –leptons via • Dominant squark pair production • Signature: at least one t (decaying hadronically) + jets + MET • mSUGRA parameters region: ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  29. B2 Squarks: t + jets + MET ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  30. B3 Squarks: scalar top Signature: 2 c-jets + MET ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  31. B4 Leptoquarks: third generation (tbtb state) M(LQ) > 180 GeV (b=1) CDF ( , ): M(LQ) > 235 GeV (b=1) First generation ( ) M(LQ)>241(256) GeV (b=1) M(LQ)>218(234) GeV (b=0.5) (combined Run I and Run II) ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

  32. B5 Perspective ITEP, Moscow 26.11.2007 For the DO Collaboration Alexey Popov (IHEP, Protvino)

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