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

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Presentation on theme: "Latest New Phenomena Results from Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 1."— Presentation transcript:

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

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

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

4 Supersymmetry Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007  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: 4

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

6 Squarks and gluinos: results Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 DataSM expectations di-jet5 3-jet6 gluino34 mSUGRA parameters 6

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

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

9 Charginos and Neutrallinos: 3l - state Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007  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: Two electrons or muons Third lepton Large MET Small cross-sections but very clean signature 9

10 Charginos and Neutrallinos: 3l - state Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 CutDataSM expectedmSUGRA Preselection118518113592 17518 Anti-Z1745918036 8913 Third Track776650 187.6 MET22.0 0.74.6 MET x pT(3)00.8 0.73.5 10

11 Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 CutDataSM expectedmSUGRA Preselection31053080 3414.4 MET303287 79.2 Isolation55.1 0.94.6 Anti-Diboson02.8 CutDataSM expectedmSUGRA Preselection8192780373 13012.1 Anti-Z74868099 537.8 MET5154 44.9 Isolation42.9 MET x pT(3)21.8 Charginos and Neutrallinos: 3l - state 11

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

13 Charginos and Neutrallinos: Like-sign  CutDataSM expectedmSUGRA Preselection1523414922 9818.4 0.6 35693479 2327.9 0.6 24.9 1.25.7 0.5 MET11.7 0.64.6 0.4 MET x pT(2)11.1 0.44.0 0.4 Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 13

14 Trilepton results Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 “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 14

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:  + MET One dimensioned parameter  – effective energy scale of SUSY breaking. Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 15

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 Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 16

17 Leptoquarks: Second Generation M(LQ) > 214 GeV (  =0.5) CDF Run II ( ) M(LQ) > 170 GeV (for  +jets) M(LQ)>208 GeV (  combined) Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 17

18 Randall-Sundrum Gravitons RS Model  Use Extra Dimensions (ED) to address a hierarchy problem  One 5 th (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  Two parameters: – mass of the first excited mode of the G – dimensionless coupling to the SM fields Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 18

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

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

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 Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 21

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 Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 22

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

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 Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 24

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

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! Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 26

27 Backup slides

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

29 Squarks:  jets + MET Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 DataSM predictionsmSUGRA 2 B2

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

31 First generation ( ) M(LQ)>241(256) GeV (  =1) M(LQ)>218(234) GeV (  (combined Run I and Run II) Leptoquarks: third generation (  b  b state) Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow 26.11.2007 M(LQ) > 180 GeV (  CDF (, ): M(LQ) > 235 GeV (  B4

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


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