Searches for Strong Dynamics at the TEVATRON Hereafter I Present Preliminary Results on Behalf of the CDF and D0 Collaborations OUTLINE I. Introduction II. Search for Excited Electrons III. Search for Z in the Dilepton Channel IV. Search for Leptoquarks V. Conclusions and Prospects
I. Introduction The TEVATRON at Run II p 1.96 TeV Chicago p 2004 highlights Record lumi: 7.83x10 31 cm -2 s -1 Best D0 store: 2.19pb -1 First stores w/ antiprotons from Recycler (commissioning) CDF p DØ Booster p source Tevatron Main Injector & Recycler p High data taking efficiency in the range 80-90% So far analyzed around 200 pb -1 / expt
I. Introduction The TEVATRON at Run II D0 (23 May 04): Del d: 451 pb -1 Rec d: 356 pb -1 data for physics April 2001 Feb 2002 first data for analyses Jul 2002 detector commissioning
Muon System I. Introduction The CDF Detector at Run II Central Calorimeter Solenoid Silicon Microstrip Tracker Plug Calorimeter Time-of-Flight Drift Chamber Front End Electronics Pipelined Triggers / DAQ Online & Offline Software New Partly New Old
I. Introduction The D0 Detector at Run II
II. Search for Excited Electrons Production Mechanisms Contact Interaction Parameters: M e* compositeness scale Λ Gauge Mediation Parameters: M e* coupling f/λ (f relative coupling to Ζ) Search Channel and Topology Channel: e ± * e ± +γ Topology: 2e+γ
II. Search for Excited Electrons Signal Acceptance MC Generators: Pythia and CompHep Contact Interaction C: η e <1.1 EC: 1.2< η EM <2.8 Gauge Mediation
Low background analysis II. Search for Excited Electrons exp :3± 0.4 obs :3 SM Background Background Process γ+z 2γ+jets WZ MC Generator ZGAMMA PYTHIA PYTHIA All comb.
II. Search for Excited Electrons Integrated Background 3-body decays 2 body-decays
II. Search for Excited Electrons Data Candidate Run 144674 Evt 4143240 p T (GeV) η det φ (rad) e 1 37-0.87 0.62 ΕΜ 1 71 1.48 4.05 ΕΜ 2 48-1.47 2.02 ΕΜ 1 ΕΜ 2 e 1 e 1 ΕΜ 2 E/ T = 21GeV M(e 1 +ΕΜ 1 ) M(e 1 +ΕΜ 2 ) M(ΕΜ 1 +ΕΜ 2 ) M(e 1 +ΕΜ 1 +ΕΜ 2 ) 176 GeV 61 GeV 257 GeV 318 GeV
II. Search for Excited Electrons Exclusion Limits Contact Interaction M(e M(e ) > 889 GeV (obs) ) > 889 GeV (exp) * * For M e* =Λ,
II. Search for Excited Electrons Exclusion Limits Gauge Mediation For M e* = Λ, M(e M(e * * ) ) > > 208GeV (obs) 224 GeV (exp)
III. Search for Z in the Dilepton Channel Introduction Expected in models like: + Technicolor: ρ TC / ω TC, techni-meson mass M TC Z H + Little Higgs:, SU(2) Z H coupling parameter cotθ Sequential Z : ref. Model w/ SM-like couplings to leptons, sole parameter M Z Searches at the TEVATRON Run II CDF: acceptances and model for resonances as a function of new particle spin 0,1,2 search in high mass ee and µµ channels about 200 pb -1 analyzed for each channel Limit: from fitting dilepton mass spectra D0: acceptances and model of resonances determined for each specific model search in high mass ee channel about 200 pb -1 analyzed Limit: using mass window cuts and counting experiment
III. Search for Z in the Dilepton Channel Select 2 high p T isolated electrons (at least 1 track match) Overall efficiencies: ε CC 0.74± 0.02, ε = 0.74± 0.02 Main backgrounds at high mass: γ*/z (MC) QCD fakes (data) EC D0 Dielectron Channel = EC EC Total 14195 CC- CC 8246 CC- EC 5949 QCD fakes Signal acceptance: Pythia 6.2 and CTEQ5L Fast parametrized simulation for detector response 600 GeV Z
III. Search for Z in the Dilepton Channel D0 Dielectron Channel Systematic uncertainties: Several cancellations in the Z to Z cross section ratio Integrated lumi: 6.5% Signal syst. Uncert. K-factor E T, η depend. Accpet. Total 10% 7% 5% 13% Bkgd syst. QCD D-Y Uncert. 10% 10% Results: Obs: 0 Exp: 1.9
III. Search for Z in the Dilepton Channel Highest mass candidate: D0 Dielectron Channel E/ 8.8 T Type e + /e - E T1 239.2 E T2 226.9 η 1-0.45 η 2-0.50 φ 1 0.48 φ 2 3.68 M 475 cosθ 0.01
III. Search for Z in the Dilepton Channel Most stringent limit to date M Z >780 GeV (95% CL)
III. Search for Z in the Dilepton Channel 2e in CC-CC, CC-EC, EC-EC: p T > 25 GeV at least 1 track match CC: η e <1.1 EC: 1.2< η ΕΜ <2.8 CDF Dielectron Channel Accept. Spin 1
III. Search for Z in the Dilepton Channel Results: CC-CC: Obs: 0 Exp: 1.4 EC-EC: Obs: 0 Exp: 0.10+/-0.03 CDF Dielectron Channel 2 Tracks!!
III. Search for Z in the Dilepton Channel CDF Dielectron Channel
III. Search for Z in the Dilepton Channel CDF Dielectron Channel
III. Search for Z in the Dilepton Channel Muons CC-CC, CC-EC: p T > 20 GeV Isolated 1st: η <1 2nd: η <1.5 CDF Dimuon Channel Accept. Spin 1
III. Search for Z in the Dilepton Channel CDF Dimuon Channel Results: Obs: 0 ; Exp: 1.03
III. Search for Z in the Dilepton Channel CDF Dilepton Combined Limit
Production: qq/gg - >LQ+LQ (dominant) about 30% increase wrt Run I Decay: λ unknown coupling to l/ν and q β=br(lq->lq) Channels: LQ->lqor νq β 2 2β(1 β) (1 β) 2 IV. Search for Leptoquarks Introduction Scalar LQ: σ only depends on M LQ Vector LQ: σ also depends on 2 anom. couplings
IV. Search for Leptoquarks CDF 2j+E T Channel Event Selection: 2 or 3 jets: E T (j 1 ) > 40 GeV; E T (j 2 ) > 25 GeV ; E T (j 3 ) > 7 GeV E T > 55 GeV η 1,2 <1.0; η 3 <2.5 no other jets w/ E T > 7 GeV 100 o < φ(e T, j 1,2 ) < 165 o 80 o < φ(j 1, j 2 ) < 165 o 100 o < MIN φ(e T, j 2,3 ) < 165 o reject events w/ leptons 0.1 < EMF(j) < 0.9 at least 4 tracks in jet E/ T
Results: Obs: 124 Exp: 118.3+/-14.5 IV. Search for Leptoquarks CDF 2j+E T Channel
IV. Search for Leptoquarks CDF 2j+2e Channel Event Selection: 2 CC electrons w/ E T > 25 GeV at least 1 track match reject events w/ 76 < M ee < 110 GeV E T (j 1 )+ E T (j 2 ) > 85 GeV E T (e 1 )+ E T (e 2 ) > 85 GeV sqrt([e T (j 1 )+ E T (j 2 )] 2 + [E T (e 1 )+ E T (e 2 ) ] 2 ) > 200 GeV Background: ttbar in 2e channel: 0.25+/- 0.03 (Pythia) γ*/z+2j: 3.13+/- 2.8 (Alpgen+PS) Exp: 3.39+/-3.15 Obs: 0
Event Selection: 1 CC electron w/ E T > 25 GeV E T > 30 GeV; E T /sqrt(h T ) > 4.5 M T (E T, e) > 120 GeV E T (j 2 ) > 30 GeV E T (j 1 )+ E T (j 2 ) > 80 GeV φ(e T, j) > 10 o reject 2e events 1 track match Background: ttbar in 2e channel: 0.13+/- 0.02 (Pythia) ttbar in l+jets channel: 0.026+/- 0.012 (Pythia) W+2j: 1.60+/- 1.10 (Alpgen+PS) Exp: 1.73+/-1.47 Obs: 2 IV. Search for Leptoquarks CDF 2j+e+E T Channel
IV. Search for Leptoquarks CDF LQ 1 Combined Limit
IV. Search for Leptoquarks CDF 2j+2µ Channel Background: γ*/z+2j, top and fakes Event Selection: 2µ (1 tight, 1 loose) p T (µ 1,µ 2 ) > 25 GeV Veto M µµ < 15 GeV Veto 75 < M µµ < 105 GeV p T (j 1 ) > 30 GeV; p T (j 2 ) > 15 GeV p T (j 1 ) + p T (j 2 ) > 80 GeV p T (µ 1 ) + p T (µ 2 ) > 80 GeV sqrt([p T (j 1 )+p T (j 2 )]²+ [p T (µ 1 )+p T (µ 2 )]²) > 200 GeV
IV. Search for Leptoquarks Results: Obs: 2 Exp: 3.17+/-1.17 CDF 2j+2µ Channel
IV. Search for Leptoquarks Event Selection: EM: p T > 25 GeV N EM >1; CC-CC or CC-EC at least 1 track match veto 80 < M ee < 102 GeV Global: H T > 450 GeV D0 2e+2j Channel Jets: N j >1 p T > 25 GeV η j <2.4 L dt = 175 ± 11pb Background: QCD fakes (data) γ*/z+jets (Alpgen+PS) ttbar in dielectrons (Pythia) 1
IV. Search for Leptoquarks D0 2e+2j Channel M ee =497 GeV H T =397 GeV (*) p T (EM)=130; 129; 22 GeV p T (jets)=71; 28 GeV ΕΜ 2 ΕΜ 3 j 1 j 2 ΕΜ 1
IV. Search for Leptoquarks Results: Obs: 0 Exp: 0.4+/-0.1 D0 2e+2j Channel
L dt = 175 ± 11pb IV. Search for Leptoquarks 1 D0 e+e T +2j Channel Event Selection: Background: EM: Jets: QCD fakes (data) N EM >0 N j >1 W+jets (Alpgen+PS) p T > 35 GeV p T > 25 GeV ttbar in e+jets (Pythia) CC or EC η j <2.5 1 isolated track match Global: E T > 30 GeV; φ(ν, e)>0.7; M T (e,ν)>130 GeV; H T >330 GeV
IV. Search for Leptoquarks Results: Obs: 2 Exp: 4.7+/-0.8+/-0.3 D0 e+e T +2j Channel M LQ >194 GeV
IV. Search for Leptoquarks D0 LQ1 Combined Limit
VI. Conclusions Search for Excited Electrons Me*=Λ (95% CL) Observed Limit Expected Limit Contact Interaction 889 889 Gauge Mediation 208 224 LEP (ADLO): 1.15/fb f/λ=0.1 Me*>200 GeV
VI. Conclusions Search for Z in Dileptons Expt Channel CDF ee CDF µµ CDF ee D0 ee D0 µµ... L dt (pb 1 ) Model 200 Little Higgs 200 Little Higgs 200 SM-like 200 SM-like (122) SM-like Observed Limit (GeV) 825 790 750 780 (719)
Expt Channel CDF LQ 1 pairs->e T +2j CDF LQ 1 pairs-> 2e+2j / e+e T +2j / E T +2j CDF LQ 2 pairs-> 2µ+2j D0 LQ 1 pairs-> 2e+2j / e+e T +2j VI. Conclusions Search for Leptoquarks BR Observed L 1 dt (pb ) Limit (GeV) 191 not in [78,117] 72 β=0.1 β=0.5 β=1.0 135 197 232 (220) (3*) 198 β=1.0 241 β=0.1 155 (110) 175 β=0.5 213 (204) β=1.0 238 (225) (3*) Run I
VI. Prospects The TEVATRON Integrated Luminosity (pb -1 ) 300 250 200 150 100 FY04 (as of June 3 rd, 2004): Delivered 196.9 pb -1 Design goal 305.9 pb -1 needed 9.6 pb -1 /week Base goal 229.7 pb -1 needed 2.9 pb -1 /week FY04 FY03 FY02 FY04 Design FY04 Base 50 0 0 30 60 90 120 150 180 210 240 270 300 330 360 Days Since October 1
BACK UP
I. Introduction The TEVATRON at Run II
II. Search for Excited Electrons SM Background In case the new signal undergoes 3-body decay
III. Search for Z in the Dilepton Channel CDF Dielectron Channel
IV. Search for Leptoquarks CDF 2j+E T Channel Signal region: E T > 60 GeV 80 o < φ(j 1,j 2 ) < 165 o No lepton (electron, muon) candidate (N l = 0) Control regions:
IV. Search for Leptoquarks Introduction