1 Gérard SAJOT PASCOS July 2007 Imperial College London Beyond the Standard Model Searches at the Tevatron Gérard Sajot LPSC Grenoble On behalf of the CDF and D0 Collaborations

2 Gérard SAJOT PASCOS July 2007 Imperial College London 2 OutlineOutline  Recent CDF and D0 results from “RunIIa”  1.1 fb -1  (April 2002-February 2006)  - Leptoquarks  - Compositness lepton  - 4 th generation of quarks  - Extra Gauge Bosons W’ Z’  - Extra Dimensions Monojets, di-leptons and di-photons   Not covered in this talk :  - SUSY : talk by Volker Buescher (plenary July 4th)  - Technicolor, Little Higgs  - …  See also CDF+D0 talk by Tommaso Dorigo (parallel session July 3rd)

3 Gérard SAJOT PASCOS July 2007 Imperial College London 3 LeptoquarksLeptoquarks LQ : predicted by models Beyond Standard Model (GUTs, Technicolor, SUSY..)  Color-triplet scalar (spin=0) or vector (spin=1) bosons carrying lepton and quark quantum numbers  Three generations, each coupling to one lepton generation only (lepton number violation, FCNC) LQ Production at Tevatron: dominant q qbar/g g -> LQ LQbar  scalar leptoquarks :  (  s, m SLQ )  vector leptoquarks :  (  s, m VLQ,  G, G ) At Tevatron searches are mainly for pair production of Scalar LQ -> CDF VLQ 3 2  +2b (322 pb -1 ) M > 251 GeV (minimal coupling) M > 317 GeV (Yang-Mills coupling) submitted -> D0 : single production of SLQ2 for a luminosity of 300 pb -1 PLB 647, 74 (2007) -> more on back-up slides

4 Gérard SAJOT PASCOS July 2007 Imperial College London 4 2 nd generation LQ D0 1 fb -1 LQ2LQ2   q  q Background : ->W+jets, Z+jets -> ttbar -> QCD : from data Basic Selection : - 1  |  | 20 GeV - at least 2 jets |  | 25 GeV - MET> 30 GeV (not aligned with  to minimize mis-measured MET) - M T (  ) > 50 GeV (to reject QCD background)  = BF(LQ2 ->  q) Br( LQ2LQ2   q  q)= 2  (1-  )

5 Gérard SAJOT PASCOS July 2007 Imperial College London 5 2 nd generation LQ D0 1 fb -1 Optimized cuts (done for m(LQ) = 200 GeV) : - M T (  ) > 160 GeV (W background) - Scalar Transverse Energy S T = p T (  )+p T (jet1)+p T (jet2)+MET>350GeV - M(  jet1) > 150 GeV (related to LQ mass)  - the  jet combination with the invariant mass closest to the searched LQ :  |M(  jet) rec -M(LQ) gen | < 100 GeV D0 at 95%CL M SLQ2 >214 GeV for  =0.5 D0 Data6 Total Bkg6.4  0.7  0.8 Efficiency m LQ =200 GeV   Previous SLQ2 results 170 GeVCDF RunII  jj198 pb GeVCDF RunII combined  jj and  jj and  jj 198 pb GeVD0 RunII combined 294 pb -1

6 Gérard SAJOT PASCOS July 2007 Imperial College London 6 Search for f*  Several models postulate that quarks and leptons are composed of scalar and spin-1/2 particles :  -> large spectrum of excited states :  e*,  *, q*  -> contact interactions (CI) between  quarks and leptons  CDF -> e* (202 pb -1, 2005)  ->  * (371 pb -1, 2006)  D0 ->  * (380 pb -1, 2006)  -> e* for the first time - production via CI  - decay via gauge interaction (e*->e ,   W, eZ) or CI e*->effbar)  Search in ee 

7 Gérard SAJOT PASCOS July 2007 Imperial College London 7 Search for e* D0 1.0 fb -1 Selection : - trigger on single or di-electron - 2 isolated electrons with  E T > 25 GeV, E T > 15 GeV - 1 isolated photon with E T > 15 GeV Background dominated by - DY+  -> ee  - DY+jet -> ee “fake  ” Estimated from ee data Search for a peak in m e  Data : 259 events Total Background 232  3  29 events Expected if m e* = 300 GeV

8 Gérard SAJOT PASCOS July 2007 Imperial College London 8 Search for e* D0 1.0 fb -1 D0 limits at 95% CL m e* > 756 GeV for  = 1 TeV m e* > 946 GeV when neglecting CI decays and for  = m e* improving previous CDF RunII limit me* > 879 GeV 202 pb -1  Parameters : m e*,  (compositeness scale)

9 Gérard SAJOT PASCOS July 2007 Imperial College London 9 4 th generation quark : b’ ->bZ CDF 1.1 fb -1 4 th generation quark : b’ ->bZ CDF 1.1 fb -1  b'b‘bar -> bZbZ -> bllbqq (l=e or  )  Selection :  - blind analysis  - Z->ee or , p T (z) >20 GeV  - N jet 30  3 (number of jets  E T > 30 GeV, |  |<2)  - J T 30 > X ( J T 30 = scalar sum of E T  of all jets in the event  with E T > 30 GeV and  |  |<2) Background : Z+jets Predicted from the data by fitting the ET distributions in N jet 30 =1 and 2 and modeling J T 30.  10% uncertainty on acceptance X efficiency  (dominated by 6.7% Jet Energy Scale) CDF M b’ > 270 GeV if BR(b’->bZ)=100%

10 Gérard SAJOT PASCOS July 2007 Imperial College London 10 W’->e  D0 900 pb -1 W’->e  D0 900 pb -1 Predicted in many beyond-SM scenarios: Left-Right-Symmetric models, GUT models which may also imply SUSY (e.g E_6), … Search assumes : - a SM-like W’ (same couplings). -  w’ = 4/3 m w’ /m w  w (factor 4/3 if w’->tbbar is possible, i. e. m w’ > 180 GeV) Selection : - isolated central electron (|  |<1.1) E T > 30 GeV - MET > 30 GeV Background : - W-> e ,  - WW, WZ, ZZ, ttbar - QCD background estimated from data (low m T region)

11 Gérard SAJOT PASCOS July 2007 Imperial College London 11 W’->e  D0 900 pb -1 W’->e  D0 900 pb -1 Further selection : m T > 150 GeV ->Data : 630 events ->Total Background : 623  18(stat) (syst) events D0 Limit : binned likelihood of M_T distribution M W’ > 965 GeV

12 Gérard SAJOT PASCOS July 2007 Imperial College London 12 Search for resonant tbbar production W’ -> tbbar -> Wbbar –>l  jj Method : use the single top samples and same W+jets event selection Selection : - exactly 1 lepton (e or  ) P T > 20 GeV - MET > 25 GeV - 2 or 3 jets E T >15 GeV |  |<2.8 - at least 1 jet with a displaced secondary vertex CDF Limits at 95% CL : Interference W/W’ neglected (m w’ >> m w ) L-handed and R-handed W’ models - if M  R < M W’ W’ R can decay to R-handed leptons -> M W’ > 760 GeV -if M  R > M W’ -> M W’ > 790 GeV W’ resonances W’-> tb CDF 955 pb -1 D0 : PLB 641, 423 (2006) 230 pb -1 Mw’ > 610 or 670 depending on model

13 Gérard SAJOT PASCOS July 2007 Imperial College London 13 Z’->ee CDF 1.3 fb -1 Z’->ee CDF 1.3 fb -1 Selection : - 2 electrons E T > 25 GeV at least one in central calo (|  |< 1.1) Background : Dominated by Drell Yan (irreductible) Smaller contribution from di-jet, W+jet, W+ ,  CDF : are excluded at 95% CL Z’ SM < 923 GeV E6 : Z I < 729, Z  < 822, Z  < 822, Z  < 891 GeV

14 Gérard SAJOT PASCOS July 2007 Imperial College London 14  Gravity is localised on a (3+1)-dimensional brane, the Planck brane, separated from the standard model brane in a 5 th dimension with warped metric.  In simplest version : only graviton can propagate in the 5 th dimension  Due to the warped metric their wave functions are exponentially suppressed away from the Planck brane (so gravity appears weak)  Gravitons appear as KK excitations Parameters of the model : - M1, the mass of the first excitation - the dimensionless coupling to the standard fields 0.01 <  (8  ) 1/2 /M Pl < 0.1 (limits : consistency with electroweak data and model remains perturbative) Graviton decays to ffbar and to diboson pairs. Br(G->  )= 2 Br(G->ee) spin G=2 Randall-Sundrum Gravitons

15 Gérard SAJOT PASCOS July 2007 Imperial College London 15 RS Gravitons G->ee or G->  Selection : - 2 central (|  | < 1 electromagnetic objects with E T > 25 GeV Background : - DY and di-photon (PYTHIA) - QCD estimated from data m ee and m  combined Example :  search Selection : - 2 photons with E T > 15 GeV - m  > 30 GeV Background : - SM di-photon (Diphox) - QCD jets faking photons estimated from data CDF fb -1 D0 1.1 fb -1

16 Gérard SAJOT PASCOS July 2007 Imperial College London 16 RS Gravitons G->ee and/or G->   (8  ) 1/2 /M Pl M 1 limit (GeV) Best direct limit to date D0 CDF  (8  ) 1/2 /M Pl = 0.1 M 1 limit (GeV) ee alone807 ee+  889 The area below the dashed-dotted line is excluded from the precision electroweak data CDF fb -1 D0 1.1 fb -1

17 Gérard SAJOT PASCOS July 2007 Imperial College London 17 RS G->ZZ->4e CDF 1.1 fb -1 Data : 0 events with m 4e > 500 GeV Background : 0  0.02 Signature : Four electron mass peak Discriminating variables : m 4e and  2 Event display of the lowest  2 event

18 Gérard SAJOT PASCOS July 2007 Imperial College London 18 Arkani-Hamed,Dimopoulos and Dvali LED Events with Large Missing Transverse Energy and one or more jets are predicted in many models beyond the Standard Model : - SUSY with R-parity conservation, - Technicolor (with technirhos decaying into W and Z) - leptoquarks (decay in neutrinos +jets) - Models with compactified LED  CDF search ADD MODEL :  gravity propagates in the 4 + n dimensional bulk of space-time  other SM fields are confined in the 3+1 brane If compactification on a torus, the effective Planck scale M D and the radius R n of the extra dimensions are related by : R n = 1/8  (M Pl /M D ) 2 /M D n If R large enough (O(10  m)), M D could be of the order of 1 TeV Production at Tevatron : q+qbar/g+g  G+g, q+g  G+q G escapes undetected in the bulk of ED G KK g q q g g g -> topology single jet + MET

19 Gérard SAJOT PASCOS July 2007 Imperial College London 19 ADD LED CDF 1.1 fb -1 Signature : jets+ MET Selection : - leading Jet E T > 150 GeV - MET > 120 GeV - allow 2 nd Jet with E T < 60 GeV - no 3 rd Jet with E T > 20 GeV Results: Nobs= 779 Nbkg=819  71 mainly Z(   )+jets nM D TeVR mm 2>1.33 <0.27 3>1.09 < >0.99 < >0.92 < >0.88 < LEP  + MET ICHEP 2004 CDF 95% CL

20 Gérard SAJOT PASCOS July 2007 Imperial College London 20 ConclusionsConclusions  CDF and D0 have performed new (and unsuccessful) searches in many areas for a Lumi ~ 1fb -1 (RunIIa dataset)  Not every conceivable model has been probed, but most final states  Tevatron, CDF and D0 are performing well  Analysis are improving  By the end of 2009, Tevatron is expected to deliver 6 to 7.5 fb -1 CDF and D0 have excellent physics prospects before first LHC results !

21 Gérard SAJOT PASCOS July 2007 Imperial College London 21 Back-upBack-up

22 Gérard SAJOT PASCOS July 2007 Imperial College London 22 Tevatron is performing very well CDF and D0 experiments have collected more than 3 fb -1 Record Peak luminosity above cm -2 s -1 Peak luminosity

23 Gérard SAJOT PASCOS July 2007 Imperial College London 23 Run IIa (tracking in B-field) Silicon detector Fiber tracker, preshowers Run IIa Muon system, CAL Electronics DAQ, (track) trigger system Displaced-vtx trigger p Electronics TrackerSolenoid Magnet 3 Layer Muon System Preshowers p The D0 Detector

24 Gérard SAJOT PASCOS July 2007 Imperial College London 24 The CDF Detector Addition or Improvments for the Run IIA  Si tracker  Central drift chamber 4th generation quark : b’ ->bZ CDF 1.1 fb-1  TOF 4th generation quark : b’ ->bZ CDF 1.1 fb-1  Secondary vertex trigger Addition or Improvments for the Run IIA  Forward calorimeters: "plugs" (1<|  |<3)  Extended  coverage

25 Gérard SAJOT PASCOS July 2007 Imperial College London 25 Recent RunIIa LQ searches at Tevatron ChannelL int (pb -1 )Status SLQ 2 pairs   + +2q Prel. this talk LQ 3 pairs  2 +2b31007 Sub LQ 2 pairs   2  +2q LQ 2 +   2  +q 30007Pub. LQ pairs  2 +2q37006 Pub. LQ 2 pairs  2  +2q29006 Pub. LQ 1 pairs  2e+2q LQ 1 pairs  e+ +2q Pub. ChannelL int (pb -1 )Status VLQ 3 pairs  2  +2b32207 Sub SLQ 2 pairs  2  +2j19804 Pub SLQ 2 pairs   +2j19804 Pub SLQ 1 pairs   e+2j20004 Pub SLQ 1 pairs  e+ +2j20004 Pub SLQ 1 pairs  2 +2q19103 Pub Scalar LQ 1 pairs : comb. 3 analyses above ~20005 Pub. Scalar LQ 2 pairs : comb. 2 analyses above ~20006 Pub. CDF D0 Sub= submitted Pub. = Published, Prel. = Preliminary