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B. HeinemannSearches for New Physics at the Tevatron 1 B. Heinemann University of Liverpool From Tevatron to the LHC Cosenors House, 24-25.04.2004.

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Presentation on theme: "B. HeinemannSearches for New Physics at the Tevatron 1 B. Heinemann University of Liverpool From Tevatron to the LHC Cosenors House, 24-25.04.2004."— Presentation transcript:

1 B. HeinemannSearches for New Physics at the Tevatron 1 B. Heinemann University of Liverpool From Tevatron to the LHC Cosenors House, 24-25.04.2004

2 B. HeinemannSearches for New Physics at the Tevatron 2 Outline Introduction Higgs SUSY High mass dileptons: Z and LEDs Conclusions and Outlook Other results on: Leptoquarks, Magnetic Monopoles, ADD LEDs, Excited electrons, … Difficulties: XXX YYY

3 B. HeinemannSearches for New Physics at the Tevatron 3 The Tevatron: Run 2 Data Recording Efficiency 90% efficiency Expect 2 /fb by 2006 and 4.4-8.6 /fb by 2009 sensitivity to New Physics improved by>5 compared to Run 1 Run 2 started in June 01: CMS energy 1.96 TeV Delivered Lumi: 480/pb Promising slope in 2004! Data taking efficiencies about 90% Physics Analyses: Use about 200/pb (2x run 1) But its still early days in Run 2!

4 B. HeinemannSearches for New Physics at the Tevatron 4 The Challenge Higgs ? WW, W γ, Z γ, Cross Sections (fb) QCD and EWK cross sections 10-5 orders of magnitude larger than new physics! Finding the needle in the heystack… Good understanding of SM backgrounds Use data and MC to estimate them Useful: new enhanced LO MCs (Alpgen, Madgraph) NN and Likelihood methods require excellent modelling of BG

5 B. HeinemannSearches for New Physics at the Tevatron 5 Higgs Standard Model SUSY: Enhanced production at high tan Bosophilic Higgs: hγγ Doubly Charged Higgs Backup slides

6 B. HeinemannSearches for New Physics at the Tevatron 6 Standard Model Higgs Cross sections small: 0.1 - 1 pb M H 135 GeV: decay into bb gg H: QCD BG too large HW and HZ associated production have lower (but still large!) BG Best channels: Wh lνbb Zh ννbb M H >135 GeV: decay into WW gg H WW ( * ) l + l - final states can be explored BR only 1% In this talk (both done by CDF and D0): Wh lνbb (CDF) h WW (D0) H bb H WW (*) Dominant decay modes Production Cross section

7 B. HeinemannSearches for New Physics at the Tevatron 7 Prospects for SM Higgs Original study in 1998 confirmed in 2003 Study still based on some extrapolations No sensitivity expected with current Luminosity of 200/pb (not even on plot!) But search now anyway: Get ready for high Luminosity Possibly new bright students develop smarter ideas than anticipated in studies Understand systematic errors realistically (and start working on them!) 2009 2006 E.g. SM Higgs at 115 GeV exclude at 95% C.L. in 2006 3 evidence in 2009

8 B. HeinemannSearches for New Physics at the Tevatron 8 Event selection Central isolated e/ p T > 20 GeV Missing E T > 20 GeV Two jets: E T > 15 GeV, | | < 2 Veto Di-lepton, extra jet, etc. Observe 2072 events in data Simulations performed with Alpgen plus Herwig passed through detailed detector response CDF: WH lvbb (I) Data in good agreement with Background expectation Main Background: W+light jets now require b- tag

9 B. HeinemannSearches for New Physics at the Tevatron 9 Require at least one b- tagged jet Observe 62 events in data Expect 61 ± 5 events Main contributions to background Mass Resolution: 17% Expect 0.3 evts from Higgs –Signal acceptance ~ 1.8% for M H = 110 – 130 GeV MistagsWc(c)WbbQCDtop 141312109 CDF: Higgs: WH lvbb (II)

10 B. HeinemannSearches for New Physics at the Tevatron 10 Set limits on the Higgs production cross section times branching ratio: WH ×BR(W lv, h bb) < 5 pb (D0: <12.4 pb at mh=115 GeV) Systematics studies Exceeds CDFs Run I limit ×BR < 14 – 19 pb for M H = 70 – 120 GeV PRL 79, 3819 (1997) Expect improvements due to Di-jet mass resolution (17% 12-10%) More sophisticated analysis techniques Cut and b-tag optimisation SourceError (%) ISR / FSR19 Secondary vertex8.6 Lepton ID5 Jet energy scale3 PDF1 Trigger0.7 Total22 CDF: Higgs: WH lvbb (III) Difficulties: 3 rd jet veto introduces large syst. Error due to ISR/FSR jet energy resolution: optimise in Z bb long term: need to use NN or so how reliable is MC?

11 B. HeinemannSearches for New Physics at the Tevatron 11 D0: H WW ( * ) l + l - Event selection include Isolated e/ p T (e 1 ) > 12 GeV, p T (e 2 ) > 8 GeV p T (e/ 1 ) > 12 GeV, p T (e/ 2 ) > 8 GeV p T ( 1 ) > 20 GeV, p T ( 2 ) > 10 GeV Reduce Drell-Yan background: E T >20 GeV (ee, e ); 30 GeV ( ) Veto on Z resonance Reduce top background Veto energetic jets Data correspond to integrated lumi. of ~ 180 (ee), 160 (e ) and 150 ( ) pb -1 Higgs Signal

12 B. HeinemannSearches for New Physics at the Tevatron 12 Higgs mass reconstruction not possible due to two neutrions Employ spin correlations to suppress the bkgd. (ll) variable is particularly useful Leptons from H WW ( * ) l + l - tend to be collinear D Ø : H WW ( * ) l + l - W+W+ e+e+ W-W- e-e- n (ll) between e and (after preselection cuts) Higgs of 160 GeV

13 B. HeinemannSearches for New Physics at the Tevatron 13 Number of events after selections Dominant bkgd. in e sample D Ø : H WW ( * ) l + l - Expect 0.11 events for 160 GeV SM Higgs now WWW+jetsWZtt 2.51±0.050.34±0.020.11±0.010.13±0.01 eee Observed225 Expected2.7±0.43.1±0.35.3±0.6 Excluded cross section times Branching Ratio at 95% C.L. DØ Run II Preliminary Higgs of 160 GeV

14 B. HeinemannSearches for New Physics at the Tevatron 14 Higgs in SUSY at high tan Standard Model: σ(bbH) =1-10 fb: 100 x smaller than WH SUSY: Cross section enhanced at high tanβ: σ(bb ) ~ tanβ! (Willenbrook et al.) E.g. for M(A)=120 GeV: 5 discovery for tan >30 3 evidence for tan >20 Experimentally: 1 b-jet typically soft: Require 3 jets with b-tags CDF Run I 95% C.L. ( =h,H,A) BR( ) ~ 90%

15 B. HeinemannSearches for New Physics at the Tevatron 15 D0: Neutral Higgs at High Tan Event Selection: At least 3 jets: E T cuts on jets optimized for different Higgs mass values 3 b-tagged jets Look for signal in the invariant mass spectrum from the two leading b- jets Main Background: QCD multi b-production Difficult for LO MC: determined from data and/or ALPGEN 1.2 Signal acceptance about 0.2-1.5% depending on Mass Ldt=131 pb -1 AND FINAL STATE?????????? Difficulties: triggering: 3 b-jets, 4 th jet soft: e.g. =2 % in CDF background: 3 b-jets beyond LO MC abilities and generating enough MC challenging CPU wise mass resolution: optimise and check in Z bb

16 B. HeinemannSearches for New Physics at the Tevatron 16 D0: Non-SM Light H Some extensions of SM contain Higgs w/ large B(H ) Fermiophobic Higgs : does not couple to fermions Topcolor Higgs : couples to only to top (i.e. no other fermions) Important discovery channel at LHC Event selection 2 Isolated s with pT > 25 GeV | |<1.05 (CC) or 1.5<| |<2.4 (EC) p T ( ) > 35 GeV (optimised) BG: mostly jets faking photons Syst. error about 30% per photon! Estimated from Data Ldt=191 pb -1 Central-CentralCentral-Forward

17 B. HeinemannSearches for New Physics at the Tevatron 17 Photon Fake Rate Rate of jets with leading meson (pi0, eta) which cannot be distinguished from prompt photons: Depends on detector capabilities, e.g. granularity of calorimeter Cuts! Systematic error about 30-80% depending on Et Data higher than Pythia and Herwig Pythia describes data better than Herwig CDF (preliminary result)

18 B. HeinemannSearches for New Physics at the Tevatron 18 Perform counting experiments on optimized sliding mass window to set limit on B(H ) as function of M(H) Non-SM Light Higgs H Difficulties: jets faking photons: leading pi0s NLO MC of SM necessary: Pt( ) cut

19 B. HeinemannSearches for New Physics at the Tevatron 19 Supersymmetry Reminder SM Fermions Boson Superpartners SM Bosons Fermion Superpartners Physical SUSY sparticles: neutralinos (Higgs, Photon, Z partners), charginos (Higgs, W partners), squarks (quark partners), sleptons (lepton partners) Different SUSY models: Supergravity: SUSY broken near GUT scale GUT scale parameters: scalar mass m 0, gaugino mass m 1/2, ratio of Higgs v.e.vs tanβ, Higgs mixing parameter μ LSP is neutralino or sneutrino ν Gauge-mediated models (GMSB): SUSY broken at lower energies – breaking scale important parameter. Gravitino G is the LSP (NLSP χ 0 Gγ ) ~ ~ ~

20 B. HeinemannSearches for New Physics at the Tevatron 20 Trilepton Search Chargino+neutralino production: three leptons and missing energy signature Main challenge - weak production low cross sections LEP limits are very restrictive select two identified leptons, so far: ee eμ μ ± Add Et cut and topological cuts Require an additonal isolated track Sensitive to taus too At high tan >10 stau may be light Chargino and neutralino decay into staus which then decay into taus 3-tau final state: dedicated analysis required (not covered here) /

21 B. HeinemannSearches for New Physics at the Tevatron 21 D0: Trileptons: ee+lepton (I) 2 Electrons: EM cluster+track match P T >12 (8) GeV | |<1.1 (3.0) 1.Anti-Z 1580GeV 4.Anti-Drell Yan Missing E T >20GeV (e,E T )>23 degrees 5.Isolated Track: P t >3 GeV 6.E T x P t > 250 GeV 2 Potential signal 175pb -1 / Cuts reduce BG by 4 orders of magnitude! ε(signal)=2-3%

22 B. HeinemannSearches for New Physics at the Tevatron 22 D0: Combined tri-leptons 3(2) events compared to 2.9(0.9) expected Run 1 cross section limit much improved Soon will reach MSugra prediction (in the best scenario with low slepton masses) ChannelDataBackgroundSignal e e l10.3 0.40.8-1.6 e 12.5 0.50.7-1.0 e l00.5 0.20.6-0.9 10.13 0.040-0.4 Results: Difficulties: trigger: leptons are soft: 3 rd lepton 3 GeV! background: jets faking lepton, e.g. conversions background: difficult to make enough b MC understanding Missing Et: e.g. jet mismeasurements

23 B. HeinemannSearches for New Physics at the Tevatron 23 Squarks and Gluinos Stop quark: Maybe best discovery potential in Run 2 Theorists say it should be light Searches so far only for stable stop Unfortunately no result yet in promising decay modes in Run 2 but triggers in place and analyses ongoing! Sbottom quark pp gg bbbb bbbb pp bb bb Search for b-jets + E T Generic squarks Search for jets + E T Large QCD backgrounds must be suppressed ~~~~ LEP2 limit

24 B. HeinemannSearches for New Physics at the Tevatron 24 D0: Squarks and Gluinos Squarks and gluions: Strong production large cross section, but really large instrumental backgrounds (2 orders of magnitude over SM processes) 4 events left 2.67±0.95 expected from SM sources: 50% from Zjj -> vvjj Other BG from Wjj QCD background negligible (exponential fit to the data) 17.1 event expected for M 0 =25,M 1/2 =100GeV 2 jets E T >60 (50) GeV 30< (jet,MET)<165 o Final cuts: Missing E T >175 GeV H T >275 GeV 85 pb -1

25 B. HeinemannSearches for New Physics at the Tevatron 25 D0: Squarks and Gluinos M 0 =25GeV; A 0 =0; tan =3; <0 M(gluino)>333GeV Run 1 – 310 GeV M(squark)>292GeV Difficulties: understanding Missing Et: e.g. jet mismeasurements jet energy scale and resolution uncertainty generating enough MC to estimate QCD BG! handling large jet datasets

26 B. HeinemannSearches for New Physics at the Tevatron 26 Jet Energy Scale @ CDF Use test beam to set charged pion scale Use in situ Z ee to set pi0 scale Account for MI and UE Correct for jet to hadron level Correct for hadron to parton level (e.g. top mass) Cross checks: gamma-jet: 5% difference between Pythia and Herwig after full simulation Z-jet: statistically limited Z bb and W jj in top at Et of 50 GeV or so calibration at high Et relies on MC tuning of Response to single particles Fragmenation/radiation in MC Difficulties: understand large difference between Pythia and Herwig no calibration process in interesting region: Et>400 GeV! will be dominant error on e.g. top mass

27 B. HeinemannSearches for New Physics at the Tevatron 27 Sbottom: B-jets and E T High tan( ) scenario under study: sbottom is lighter than other squarks and gluino 4b-jets+missing energy >=3jets (E T >10 GeV) Missing E T >35 GeV 1 b-tag – 5.6+-1.4 events SM predicted - 4 observed 2 b-tags –0.5+-0.1 events SM predicted - 1 observed Difficulties: understanding Missing Et: e.g. jet mismeasurements b-tagging efficiency and purity QCD background: LO MC unreliable for multi-b production

28 B. HeinemannSearches for New Physics at the Tevatron 28 Long Lived Particles! LSP – charged particle, or NLSP – charged particle (e.g. stop) with long decay time Signature – isolated track of a rather slow particle Use TOF system: NEW in Run 2 for CDF Ensure efficient tracking: β γ>0.4 (Pt>40 for M=100 GeV) Efficiency about 1-3% BG: 2.9±3.2 Data: 7 observed Use dE/dx and COT timing in future Difficulties: cosmic background track efficiency for massive/slow particles (vc)

29 B. HeinemannSearches for New Physics at the Tevatron 29 GMSB Model Met Gauge mediated SUSY breaking scale Gravitino – LSP NLSP (neutralino) LSP Dominant SUSY mode: Signature – 2 photons, missing energy P T (photon)>20 GeV in | |<1.1 1 event survived 2.5±0.5 expected from SM Missing E T >40 GeV 185 pb -1 New D0 event taken recently: 2 γ, 1e, large Et: Et( γ )=69 GeV, Et( γ )=27 GeV Et(e)=24 GeV Et=63 GeV /

30 B. HeinemannSearches for New Physics at the Tevatron 30 GMSB Model Met Data consistent with SM background Derive upper limit on cross section Compare to NLO cross section Result: Difficulties: understanding QCD BG due to Et mismeasurement instrumental (cosmic/beam-halo) BG

31 B. HeinemannSearches for New Physics at the Tevatron 31 CDF: B s ->μ + μ - New Physics can enhance branching ratios of B-mesons: Measure BR in decay modes suppressed in SM E.g. B s μμ: B s = bound state of b and s quark SM: BR(B s μμ)~10 -9 SUSY: BR may be A LOT higher at high tan Blind analysis with a priori optimisation: 1 event observed, ~1+-0.3 expected 90% CL limits: BR(B s μμ)<5.8 X 10 -7 BR(B d μμ)<1.5 X 10 -7 SM vs e.g. SUSY

32 B. HeinemannSearches for New Physics at the Tevatron 32 SUSY Sensitivity: B s ->μμ SO(10) GUT model (R. Dermisek et al.: hep/ph-0304101) : accounts for dark matter and massive neutrinos largely ruled out by new result mSugra at high tanβ (A. Dedes et al.: hep/ph-0108037): Just about scratching the corner of parameter space In direct competition with Higgs (g-2)μ Expect <1x10 -7 by end of year start exceeding limits set by higgs 90% CL limit: BR(Bsμμ)<5.8 x 10 -7

33 B. HeinemannSearches for New Physics at the Tevatron 33 Physics Potential of Taus Light higgs decays to taus 8% of the time: E.g. for 120 GeV higgs have already 20 H ττ events on tape Decay to taus enhanced in MSSM at high tan At high tan the stau is light: Charginos and Neutralinos can decay into staus Stau may be LSP Taus are difficult at pp machines… No search result yet though but building foundations measure: Z-> tau tau W-> tau nu

34 B. HeinemannSearches for New Physics at the Tevatron 34 W τν and Z τ+τ Signals Look for hadronic tau decays Narrow isolated jet Low track multiplicity Identify π 0 candidate in ShowerMax detector invariant mass of tracks and π 0 < m(τ) Efficiency about 50% Z τ+τ signal: 1 hadronic tau decay (jet) 1 τ eν or τ μν decay Backgrounds from Z l+l, QCD Difficulties: triggering: CDF has new trigger lepton + track jets faking hadronic taus: about 0.3% right now tau ID efficiency: no clean way to get from data 2345 W τν candidates in 72/pb NNLO prediction: 2.73 nb

35 B. HeinemannSearches for New Physics at the Tevatron 35 Di-lepton Production @ High Mass Select 2 opposite sign leptons: ee or μμ ( ττ soon) Here ee channel: 2 central e (CC) 1 central and 1 forward e (CP) NEW: 2 forward es (PP) Good agreement with SM prediction

36 B. HeinemannSearches for New Physics at the Tevatron 36 Model Independent Limits: spin-0, spin-1 and spin-2 particles spin-0 spin-2 spin-1 model-independent limits on σxBR for particles with spins 0, 1 and 2 applicable to any new possible future theory Observed limit consistent with expectation New Plug-Plug result not yet included Muon analysis also ongoing

37 B. HeinemannSearches for New Physics at the Tevatron 37 Limits on Several Models Z occurs naturally in extensions of SM towards GUT scale, e.g. E6 models M(Z)>570 GeV for E6 models (depends on exact model: couplings to quarks and leptons) M(Z)>750 GeV for SM coupling Sneutrino in R-Parity violating SUSY may decay to 2 leptons: M>600 GeV for couplingxBR=0.01 Randall-Sundrum gravitons Mass> 600 GeV for k/M Pl >0.01 Techni- pions, -omegas G ν Z ~ Difficulties: Mass dependent k-factor (NNLO) for Z signal recently provided by J. Stirling No mass dependent k-factor for DY background versus di-lepton mass yet: will use MC@NLO G

38 B. HeinemannSearches for New Physics at the Tevatron 38 Summary of Black Boxes Background Monte Carlo: Enhanced LO MCs (Alpgen, Madgraph etc.) being used more and more Much better description of data than e.g. Pythia/Herwig: Starting to use MC@NLO CPU intense: often impractical to generate enough in remote corners of phase space Jet energy scale and resolution crucial for many measurements: Tuning of Pythia and Herwig required to describe jets better Jets faking leptons, photons, taus: Fake rate measurements big industry at CDF and D0: it is an art to correctly measure a fake rate! Biggest experimental problems arise when data NOT modelled by MC Generator detector simulation Input and suggestions from theorists (or anybody) to maximise physics are very very welcome!

39 B. HeinemannSearches for New Physics at the Tevatron 39 Conclusions and Outlook Have done many searches and not found anything, but This is just the beginning: expect a factor of 10 more data by 2006/7 Analyses can be optimised Understanding of detector and techniques improving New/better MC tools becoming available Identify and solve experimental and phenomenological challenges Invaluable experience for the LHC on Background estimation Jet energy and Missing Et measurements Reliability and understanding of MC and its limitations Commissioning the largest scale detectors to date Optimising triggers and handling large data samples Publishing papers now whenever result is competitive

40 B. HeinemannSearches for New Physics at the Tevatron 40 WH: compare to HSWG CDF 2CDF 1HSWG Case 0 HSWG default (M)17%15% 10% S0.270.310.13 B24.550.73.22.1 S/sqrt(B)0.0540.040.0750.090 Mh=115 GeV

41 B. HeinemannSearches for New Physics at the Tevatron 41 Its early days for searches… Analyses not yet fully optimised for maximal sensitivity: Extrapolation of current result to 2 fb -1 not valid Legacy of Run 1: going back to Run 1 required BEFORE making improvements upon Run 1 Largest scale detectors world-wide E.g. 720k RO channels for CDF Silicon detector Commissioning and maintenance take a lot of resources Optimisation of triggers still ongoing Constantly increasing Luminosity requires frequent changes to optimise physics potential Offline software and Data Handling permanent struggle Monte Carlo statistics often limited, e.g. no full survey of SUSY parameter space Development of offline tools e.g. b-tagging, jet calibration, tracking algorithms vital for long term success Requires people focussing on this rather than analyses Many (good) people focused on EWK and top measurements instead to gain understanding of detectors (quite rightly!)

42 B. HeinemannSearches for New Physics at the Tevatron 42 Doubly Charged Higgs: H ++ /H -- H ++ /H -- predicted in some extensions of SM: Left-Right (LR) symmetric models SUSY LR models : low mass (~100 GeV – 1 TeV) Single and Pair production Striking signature: decay into 2 like-sign leptons ee channel: M(ee)>100 GeV to suppress large BG from Zs (conversions: e ± e ± γe ± e + e - ) eμ and μμ channels Sensitive to single and pair production of H++/H CDF

43 B. HeinemannSearches for New Physics at the Tevatron 43 Doubly Charged Higgs: H++/H-- Blind analysis search region: M>100 GeV 0 events observed 4.3±1.3 events expected Result: 95% C.L. upper limit on cross section x BR for pair production (pp H ++ H -- l + l + l - l - ) Mass Limit CDF 240 pb -1 D 106 pb -1 H L ++ H R ++ H L ++ H R ++ ee135~102-113 13511311695 e 115

44 B. HeinemannSearches for New Physics at the Tevatron 44 Perspectives: Stops and Sbottoms Stops may be light due to mixing between partners of left, right-handed top Similar for sbottoms Look for direct pair production of stops or sbottoms Stop mass reach up to ~175GeV/c 2 Sbottom sensitivity up to 250GeV/c 2

45 B. HeinemannSearches for New Physics at the Tevatron 45 Apparent symmetry between the lepton & quark sectors: common origin ? e Lepton + Quark Resonances : Leptoquarks LQs appear in many extensions of SM (compositeness, technicolor…) Connect lepton & quark sectors Scalar or Vector color triplet bosons Carry both lepton and baryon number fractional em. Charge: +-1/3, +-4/3, etc. Braching ratio β unknown, convention: β=1 means 100% BR LQ l ± q β=0 means 100% BR LQ νq Also sensitive to e.g. squarks in RPV (exactly the same!) Nice competition between worlds accelerators: HERA, LEP and Tevatron At Tevatron: independent of coupling λ

46 B. HeinemannSearches for New Physics at the Tevatron 46 Leptoquarks: 1 st generation New analysis in run 2: Search for LQs decaying LQνq (β=1) 2 jets (Et>) and Et>60 GeV: Experimentally challenging Result: 124 events observed 118.3±14.5 events expected exclude LQ masses with 78230 GeV for β=1 (72 pb -1 ) Difficulties: understanding Missing Et: e.g. jet mismeasurements ISR and FSR uncertainties???

47 B. HeinemannSearches for New Physics at the Tevatron 47 Summary of 1 st Generation Leptoquark Results Beta 1 st 2 nd 1225200 1/2204 0 9898 1220202 1/2182164 0 123 1 Beta 1 st 2 nd 1225200 1/2204 0 9898 1220202 1/2182164 0 123 1 1 c c 3 rd generation not shown Run 1Run 2 Beta 1 st 2 nd 1.0238200 0.5213 in progress 0.0 in progressin progress 1.0230240 0.5197 in progress 0.0117117 Beta 1 st 2 nd 1.0238200 0.5213 in progress 0.0 in progressin progress 1.0230240 0.5197 in progress 0.0117117

48 B. HeinemannSearches for New Physics at the Tevatron 48 ee nalysis CDF has done a search for excited electron, predicted in many compositeness models Produce via contact or gauge mediated interactions The cross section depends on e* mass and L = 200 pb-1 2 electron / 2 electron / At least one Central electron Expected 2.98 +0.4 -0.3 ; observed: 3 first time search Contact interaction: At 95% C.L. Me*>889GeV (Me* = ) Gauge mediated: At 95% C.L. Me*>208GeV (Me*= )

49 B. HeinemannSearches for New Physics at the Tevatron 49 Jets Analysis jj channel ( =1) Two muons 2 jets M J Y Remove events in the Z peak (E t (j 1 )+ E t (j 2 ) ) > 85 GeV (P t ( 1 )+ P t ( 2 )) > 85 GeV j(E t ) 2 + (P t ) 2 >200 GeV CDF observe 2 events w/~200 pb -1 CDF expects 3.15±0.17 Upper limit at 95%C.L M LQ > 240 GeV ( =1) Second generation LeptoQuarks

50 B. HeinemannSearches for New Physics at the Tevatron 50 e Analysis DØ has done model independent search in e channel Search for an excess over the SM prediction in the kinematic space Look at the Missing E T, sensitive to new Physics Set upper limits at 95 % C.L. L = 98 pb -1 1 electron E t >25 GeV 1 muon Pt>25 GeV Good fiducial volume 0/1 jet

51 B. HeinemannSearches for New Physics at the Tevatron 51 Dilepton High Mass Analyses Search for resonances in high invariant mass Results can be interpreted under many different models: Z (E6, sequential, little higgs) Large Extra Dimensions Randall Sundrum Technicolor SUSY Etc CDF and DØ has slightly different approach: Calculate the acceptances and resonances for 3 different spin assumption( 0,1,2) and applied to many models. CDF : Calculate the acceptances and resonances for 3 different spin assumption( 0,1,2) and applied to many models. Calculate the acceptances and resonances for eachspecific model DØ: Calculate the acceptances and resonances for each specific model


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