Carmine Elvezio Pagliarone. INFN Pisa (on. IFAE 2003, Lecce 24/04/2003 Carmine Elvezio Pagliarone

Transcription

1 Carmine Elvezio Pagliarone INFN Pisa (on behalf of CDF & D0 )

2 the CDFII Collaboration CDF physicists Canada 3% Italy 20% Taiwan 3% Germany 2% Japan 9% US 63% IFAE 2003, Lecce Carmine Elvezio Pagliarone

3 Fermilab Tevatron Collider D Booster p p source Main Injector and Recycler

4 The Fermilab Accelerator Complex Main Injector (150 GeV proton storage ring) replaces Main Ring (the original accelerator); Completely revamped stochastic cooling system for antiprotons; A new permanent magnet Recycler storage ring for antiprotons; Increased number of p and p-bar p bunches : 6 36 (396 ns) Higher center of mass energy 2 TeV achived increasing the beam Energies GeV IFAE 2003, Lecce Carmine Elvezio Pagliarone

5 Tevatron Collider Improvements L = 3γ r f * β Total Antiprotons 0 ( BN ) N B N p p N N p ε p F ( ) * β, θ x, θ y, ε p, ε p, σ z ) (1 + ε ε p per bunch p p Physics Opportunites Top Higgs QCD Electroweak B Physics New Phenomena IFAE 2003, Lecce Carmine Elvezio Pagliarone

6 Tevatron Performances vs Expected Luminosity IFAE 2003, Lecce Carmine Elvezio Pagliarone

7 Status of CDF & D0 Detectors Delivered Luminosity 180 pb -1 Physics Luminosity CDF 130 pb -1 D0 84 pb -1 (since April 02) CDF Integrated Luminosity

8 Short term Luminosity Prospects Massive effort put into understanding and improving Luminosity Fixed Accumulator MI optics Much work on stabilizing tunes in injection and low beta squeeze Fight large antiproton emittances Work on accumulator lattice to reduce beam heating Max luminosity achievable without Recycler ~8x10 31 Need recycler to get to 2 x full benefits of Recycler later on IFAE 2003, Lecce Carmine Elvezio Pagliarone

9 Si tracking Endplug Calorimeter Tracking Layer 00 SVX II ISL COT Front End Electronics Trigger (pipelined( pipelined) DAQ System Muon Systems Luminosity Monitor TOF Offline Software IFAE 2003, Lecce CMX IMU CMX Mini skirt SUSY02, Hamburg COT CMP Carmine Elvezio Pagliarone

10 Central Outer Tracker (COT): open cell drift chamber maximum drift time 100ns Small cell size, Fast gas single hit resolution ~200 µm excellent pattern recognition improved stereo capabilities The CDFII Tracking System Silicon Tracker System: increased z coverage (length ~ 1m) η coverage up to η < 2 3-D track reconstruction impact parameter resolution σ φ < 30 µm σ z < 60 µm 3 different detectors: 750,000 channels L00: inner most, R= 2.5 cm, rad-hard, SS SVXII: 5 layers, 3<R<10 cm, DS (90 and sas) ISL: 2 layers, 10<R<20 cm and large η, DS IFAE 2003, Lecce COT into CDFII Trigger System: two main improvements XFT: track reconstruction at L1 SVT: displaced track triggering at L2 Carmine Elvezio Pagliarone

11 Run II detector improvements Improved z coverage of Silicon tracker +50% of Run I geometrical acceptance ( top)( 3D vertexing capabilities better fake rejection Track reconstruction can be extended to 1<η<2 <2 several major effects: b-tagging (recover ~30% of b s in tt events) lepton ID (electrons in Plug calorimeter) Increased muon system acceptance by 12% affects trigger, ID and SLT efficiency Efficiencies (%) SVX(b-jet) SLT(b-jet) Run I Run II IFAE 2003, Lecce Carmine Elvezio Pagliarone

12 CDF-II Status Detector: All systems installed and commissioned; DAQ and trigger: Running physics trigger table with > 100 trigger paths since Feb 02 New SVT very successful Typical running conditions: L1: 3.5KHz L2: 200 Hz L3: 20 Hz Data processing: Reconstruction farm keeps up with data logging Physics groups skim data: Observe signals from low and high P T triggers: J/ψ,, D, B, W, Z IFAE 2003, Lecce Carmine Elvezio Pagliarone

13 IFAE 2003, Lecce Carmine Elvezio Pagliarone

14 IFAE 2003, Lecce Carmine Elvezio Pagliarone

15 SM gioie e dolori Extremely precise But also many open questions Standard Model accomodates but does not explain: EWSB CP-Violation Fermion Masses Higgs self-coupling is positive which leads to a triviality problem that bound M H from above The natural M H value is L, the scale of new physiscs; ; if SM is the ultimate theory up to GUT scale, an extremely precise fine tuning is required;

16 Many Searches for New Phenomena SUSY in many different Scenarios: MSSM msugra 3 rd Generation/High tanβ RPV GMSB AMSB LFV also in the Higgs Sector; Large Extra Dimensions: ADD Randall-Sundrum Leptoquarks Compositness

17 Advances on Tau ID & Searches with Taus in the Final state

18 Taus in Run II Many searches with taus in the final state; Taus were traditionally more difficult for both experiments; Needs of a significant improvement; CDF Lepton+Track (LT) Triggers (5): Implemented single tau and Ditau Triggers (5): τ + MET, τ h + τ l (l= e, µ) τ h τ h lepton+track Trigger Lepton P T > 8 GeV/c e, CMUP-µ,CMX,CMX-µ; Tau-style isolated 5 GeV/c track; Targets multilepton final states including taus; Trigger was Installed and Commissioned in January 2002.

19 lepton+trk Trigger Z τ p T seed seed > 5 GeV/c Tau Cone Isolation Cone Lepton (e,( e,µ) Lower p T Threshold τ p l T > 8 GeV/c Isolated track No tracks in 10 No tracks in Cone No prescale with high luminosity!!

20 Z Event Selection Baseline selection: e+τ h e: 10 GeV, τ h : 20GeV Transverse mass cut to reduce W+jets events: M T (l,e T ) < 25 GeV/c 2 Vector Sum p T cut to reduce QCD events p T (l,e T ) > 25 GeV/c Example: Run I (e: 10GeV, τ h :15GeV) (OS l τ h + 0 jets) CDF Run I Preliminary

21 W/Z τ + τ track Multiplicity After Baseline( e / /τ h ), M T, P T cuts Data: 78 Events Z τ e τ h (fit): 46±15 evts QCD (fit): 28±14 evts Z ee (fit): 3.7 evts Data: 2345 Events

22 After Baseline( e / /τ h ), MT, M pt cuts, OS Mass (OS data) W/Z τ + τ Data : 47 evts Z τ e τ h (fix): 39 evts QCD (fit): 11±6 evts Z ee (fix): 2.8 evts Finalizing Z analysis, including the µ + µ channel

23 Z τ + τ Tau Definition: Calorimeter Cluster R=0.4 RMS(cluster size)<0.25 At least 1 track

24 SUSY Searches at Tevatron

25 RPV msugra Search in Decays of Stop Pair Stop pairs are produced thru RPC Assuming RPV only in the 3rd generation( λ ' in λ ' i j k 333 LQ D ): pp b τ ~~ t t, ( ~ t ~_ t ~ t 1 1 τ b 1 ijk bτ ) ( blν ν )( b τ ) l τ h l + τ h + b + b Trigger Dominant SM BGs Z( ττ)+ >2 jets W( lν) + >3 jets QCD _ t t Wb+Wb WW/WZ/ZZ No b-tag for Run I τ h selection (106 pb (106 pb - 1 ): τ h : cluster P T >15 GeV/c, η <1.0 <1.0 τ h ID: number of tracks and π o in a narrow cone, isolation energy, etc.

26 Additional Selections: M T (lepton,e T )< 35 GeV/c 2 H T (lepton,τ h,e T )> 70 GeV 2 jets: E T > 15 GeV channel Background Events e 1.92 ± µ 1.13 ± ALEPH Limit: m t ~ > 93 GeV/c 2

27 Run II Preliminary Results

28 2TeV σ limit1 σ σ 1 14 ε L limit2 limit1 1 = 1 ε1 L ε L 2 = σ limit pb ( ) 2fb 1 2 ε L 2 1 Mass Limit : GeV/c 2 2 Assuming same efficiency, same background level due to 1 b-tag, b naturally not observing the process

29 Cuts: 2e: P T >15(10), 10<M ee <70 M T (e,met)>15 Iso Track P T >5, η <3 <3 MET>15 Used 42 pb -1 No events observed Expected: 0.0 ±1.4 Low tanβ SUSY: trileptons ~ χ ~ 0 ~ ~ χ ν ) ( ν ~ 0 ( )( χ )( ~ 0 p p ± l ll l llχ ), l = e msugra: ( ~ ± m χ ) 1 tan β = ( ~ 0 m χ ) 2, 2 ( ~ 0 2m χ ) = 90, signµ = 1 1, µ 125 GeV

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32 Searches for New Mass Resonances ( bumps ) - Dileptons - Dijets - Diphotons

33 New Resonances in High Mass dileptons e + e - µ + µ - No excess have been observed; Data consistent with SM bkgs

34 Results in terms of Models High Mass Dileptons allow searches for new particle production. Randall-Sundrum Graviton Excited Graviton in 5 D Neutral Gauge bosons: Z Assuming SM Couplings Model Free parameters: - Mass M G - Coupling k/m PL

35 Z µ + µ - µ + µ - Typical high energy analysis: E T >20 GeV P T >13 GeV Calorimeter Iso/E T <0.1(0.2) M(e + e - ), M(µ + µ - )> 150 GeV/c 2 Total Expected SM Events: Sensitivity: ~ 1pb (µ)( ~ 1pb (e) 5.2 ± 0.3 Number of Observed Events: 4

36 µ + µ - e + e - combined Z µ + µ -

37 High Mass Dileptons searches µ + µ - e + e - 95% C.L. Limits on Randall-Sundrum gravitons

38 Search for Neutral Gauge Bosons & Randall-Sundrum Gravitons Z e+µ comb results e+µ comb results Run 1A Run 1B Run 2 till now Ldt (pb -1 ) % C.L. Limit (e( + e - ) 505 GeV/c GeV/c GeV/c 2 95% C.L. Limit (µ( + µ - ) GeV/c 2

39 Mass Resonances in Dijets start with the inclusive jet samples (75 pb - 1 ); get the 2 highest E T jets: E T (1), E T (2); η(1) < 2.0, η(2) < 2.0; tanh(( η η) 2) < 2/3 construct the dijet mass Fit the dijet mass spectrum applying a simple parameterization of the QCD background looking for statistically significant bumps in the mass spectrum; No evidence for new Particles was found on a total of ~ 75 pb - 1 of data we are still working on calibrations

40 Highest Run II Dijet Mass Event Run: Event: (Oct ) Jet 2 Jet 1 M(j,j) ) = 1364 GeV/c2 cos θ* * = 0.30 z vertex = -25 cm E T (jet 1)= 666 GeV η(jet 1)= 0.43 E T (jet 2)= 633 GeV η(jet 2) = -0.19

41 Searches for bumps and Limits Improved Results from CDF Run I limits No evidence of bumps on a total of ~ 75 pb - 1 of data dijet W 300 GeV/c 2 < M < 410 GeV/c 2 Excited Quarks 200 GeV/c 2 < M < 760 GeV/c 2 Axigluons or FU Colorons 200 GeV/c 2 < M < 1130 GeV/c 2 Color Octet Techni-ρ s 260 GeV/c 2 < M < 640 GeV/c 2 E6 diquarks 280 GeV/c 2 < M < 420 GeV/c 95% C.L.

42 Photon and Missing-E T Data Sets

43 Analysis Selection Cuts: Inclusice Di-γ Searches - 2 central γs with E T (γ 1 ), E T (γ 2 )> 13 GeV - Applied Cosmic Rays and Beam Halo removal M γγ E T Data Sample: 84 pb -1

44 Number of observed Events: 1365 Number of Events with E T > 25 GeV: 95 After all Analysis Cuts:

45 NLSP Searches for GMSB ~0 ~ ~ χ1 γ G γγ G 0 ~χ 1 Assuming has long lifetime: - two non pointing γ; - + MET Data Sample: 42 pb -1 2EM Clusters with E T >20 GeV, η <1.1 <1.1 EM clusters with same vertex Jet Cone R= 0.7 θ (Jet,MET)< 2.6 jet veto in 1< η det <1.5

46 Searches for GMSB Messenger mass scale M m =2 Λ Equiv. number of 5+5 m-fields N 5 =1 tanβ=15 sign(µ) µ)>0 Run II Limit: Run I Limit: m ~ 0 ( χ ) > 66GeV, Λ 52 1 > m ~ 0 ( χ 1 ) > 75GeV TeV

47 Searches for other species - CHAMPS - Leptoquarks

48 1 th generation scalar LQ LQ production at Tevatron q g LQ + LQ g g LQ + LQ q q LQ + LQ Search Decay LQ LQ l + l - qq, l ± νqq, ννqq Signature 2 high-p T Leptons + Jets 1 Isolated lepton + E T + Jet E T + jets

49 1 th generation scalar LQ Search performed in the dielectron + jet channel Search Expected Bkg Events: 3.4 ± 3.2 events Observed: 0 M(LQ) < 230 GeV/c 2

50 CHArged Massive ParticleS used the TOF Detector

51 CHAMPS - Stable Stop model considered - NLO cross section (m= M(t 1 )) 2 M ( ~ t1 ) < 107 GeV / c at 95% C.L. number of SM events Expected: 2.9 ± 0.7(stat) ± 3.1 (sys) Observed: 7

52 non SM Higgs Sector Searches

53 Search for Doubly Charged Higgs H arises in extensions of SM. At the TeVatron H can be pair-produced produced (Z exchange) or singly produced (WW fusion). Signature: same sign leptons Backgrounds are low LEP limit up to 100 GeV/c 2 ( prompt and long lived)

54 Search for Doubly Charged Same-sign dielectron mass distribution is used to search for doubly charged Higgs of a given mass search region defined as of ± 10% of Higgs mass signal region above the Z mass (>100 GeV) low mass region as control region (< 80 GeV) +0.5 Very low background (0.6( -0.1 ) W/Z + misidentified jet WZ production opposite signed mis- measured electron Higgs 0 Events observed in 91 pb -1

55 the Model Independent Approach

56 Summary and Conclusions From march 2001 both CDF and D0 are taking data; Run II Searches for New Phenomena have started; Competitive SUSY results will need more time, both in terms of luminosity and in detailed understanding of the detector efficiencies and backgrounds in the low E T region In many cases, setting competitive limits requires large luminosity and going to the low end in energies; Present analysis are already improving previous Run I results; Many new Analysis are underway; For the next several years, Tevatron is the right place where to look for new Physics

57 FINE