non susy searches at the tevatron
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Non SUSY Non SUSY Searches at the Searches at the
TevatronTevatron
XXXIXth Rencontres de MoriondXXXIXth Rencontres de Moriond
QCD and Hadronic InteractionsQCD and Hadronic Interactions
La Thuile, 28 March- 3 AprilLa Thuile, 28 March- 3 April
Rocío Vilar, IFCA (CSIC-UC)On behalf of the CDF and DØ collaborations
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 2
OutlineOutline ee/ee/ Analysis Analysis
Z’, Extra Dimensions, Technicolor, SUSY, etc. Z’, Extra Dimensions, Technicolor, SUSY, etc.
ee Analysis Analysis eeee
Excited LeptonsExcited Leptons e/e/ + Jets + Jets
Leptoquarks (First and Second generations)Leptoquarks (First and Second generations) Jets + Missing Tranverse Energy (MET)Jets + Missing Tranverse Energy (MET)
Leptoquarks (All generations)Leptoquarks (All generations) Jet + Missing Transverse Energy(MET)Jet + Missing Transverse Energy(MET)
Extra DimensionsExtra Dimensions ConclusionsConclusions
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 3
Dilepton High Mass Dilepton High Mass AnalysesAnalyses
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:
CDF : Calculate the acceptances Calculate the acceptances and resonances for 3 different and resonances for 3 different spin assumption( 0,1,2) and spin assumption( 0,1,2) and applied to many models. applied to many models. DØ: Calculate the acceptances Calculate the acceptances and resonances for eachand resonances for each specific specific modelmodel
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 4
Dilepton High Mass(ee, Dilepton High Mass(ee, ))
CDF/DØ set limits for low-energy CDF/DØ set limits for low-energy E6 models using dilepton eventsE6 models using dilepton events
Two lepton with Et(Pt)>25 GeVTwo lepton with Et(Pt)>25 GeV at least one central leptonat least one central lepton
DØ uses mass window cuts and DØ uses mass window cuts and counting experimentcounting experimentCDF fit the MCDF fit the Mllll spectrum spectrum
channel
LL
(pb(pb-1-1))
ZI 95%C.95%C.
L L (GeV)(GeV)
Z99
5%C.L 5%C.L (GeV)(GeV)
Z99
5%C.L 5%C.L (GeV)(GeV)
Z99
5%C.L 5%C.L (GeV)(GeV)
CDFeeee 200200 5757
00616100
626255
656500
126126 424255
454555
464655
494955
DØ eeee 200200 575755
646400
656500
686800
DØ preliminary 200 pb-1Upper limit 95% C.L.
780 GeV
CDF has interpreted this result in the Little Higgs model (littlest higgs model)
Predict a heavy neutral boson ZPredict a heavy neutral boson Zh h
decaying into dileptonsdecaying into dileptonsRelevant parameter is the mixing Relevant parameter is the mixing angle cotangle cot
ee: MZ’h >825 GeV (cot= 1.0)
:MZ’h >790 GeV (cot= 1.0)
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 5
Dilepton High Mass(ee,Dilepton High Mass(ee,)) Large Extra Dimensions
ADD (GRV convention) MMplpl
22 = (M = (Mplpl|3+N|)N+2|3+N|)N+2 )R )RNN=M=Ms s
N+2N+2 R RNN
N>=3 only tested at collidersN>=3 only tested at colliders The cross section is parameterized in The cross section is parameterized in
terms ofterms of = = /M/Mss
44
DØ CDF
LL
(pb)(pb)
95%C.95%C.L L
(TeV)(TeV)
LL
(pb)(pb)
95%C.95%C.LL
(TeV)(TeV)
diEm 200200 1.361.36 200200 1.111.11
diEm ( I+II)
1.431.43
100100 0.8800.880
CDF: 2 electron Et>25 GeV Fit to the Mee spectrumDØ: 2 EM objects(e/) Et>25 GeV 2 Pt>25 GeV 2D Fit to the Mll and cos*
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 6
Dilepton High Mass(ee,Dilepton High Mass(ee,) ) CDF interpret as Randall-Sundrum graviton
1 highly curved extra dimension1 highly curved extra dimension Gravity localised in the EDGravity localised in the ED Excited Kaluza-Klein gravitonExcited Kaluza-Klein graviton
Decays to leptonsDecays to leptons Relevant parameters: k/MplRelevant parameters: k/Mpl
Set upper limits at 95% C.L.ee: MG >625 GeV (k/Mpl= 0.1) @ 200 pb -1
:MG>475 GeV (k/Mpl = 0.1) @ 126 pb-1
CDF uses acceptances CDF uses acceptances
from spin2 casefrom spin2 case
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 7
Dilepton High Mass(ee,Dilepton High Mass(ee,)) DØ has done a search for TEV-1
Extra dimensions
Chiral fermions in 3DChiral fermions in 3D SM bosons propagates in extra SM bosons propagates in extra >0 dimensions, >0 dimensions,
and are equivalent to KK towers with Massesand are equivalent to KK towers with Masses MM22
nn= M= Moo22 + n + n22MM22
cc
Gives rise to mixing among SM boson and the Gives rise to mixing among SM boson and the nth modes of W/Znth modes of W/Z
First direct searchAt 95%C.L Mc > 1.12 TeV
Indirect searches:LEP: > 6.6 TeV; all: > 6.8 TeV
198 pb-1
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 8
e Analysise Analysis DØ has done model DØ has done model
independent search in eindependent search in e channelchannel
Search for an excess over Search for an excess over the SM prediction in the the SM prediction in the kinematic spacekinematic space
Look at the Missing ELook at the Missing ET , T ,
sensitive to new Physicssensitive to new Physics Set upper limits at 95 % Set upper limits at 95 %
C.L.C.L.L L = 98 pb= 98 pb-1-1
1 electron E1 electron Ett>25 GeV>25 GeV
1 muon Pt>25 GeV1 muon Pt>25 GeVGood fiducial volumeGood fiducial volume0/1 jet0/1 jet
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 9
eeeenalysisnalysis 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-1L = 200 pb-12 electron /2 electron /At least one Central electronAt least one Central electronExpected 2.98 Expected 2.98 +0.4+0.4
-0.3 -0.3 ; observed: 3; observed: 3
first time searchContact interaction: At 95% C.L. Me*>889GeV (Me* = )
Gauge mediated: At 95% C.L. Me*>208GeV (Me*= )
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 10
Color triplet bosons with Color triplet bosons with lepton and barion numbers, lepton and barion numbers, and fraction chargeand fraction charge
Predicted in several Predicted in several theories: GUT, technicolor, theories: GUT, technicolor, SUSY,etcSUSY,etc
Assume LQ couples to Assume LQ couples to lepton and quark of same lepton and quark of same generationgeneration
Pair produced at TevatronPair produced at Tevatron LQ decays:LQ decays:
LQ lq (l = e,LQ lq (l = e,) ) =1 =1 LQ LQ q q = 0 = 0
= BR(LQ lj)= BR(LQ lj)
Lepton+Jets analysis Lepton+Jets analysis Dominant at Tevatron
30% increase in cross section at RunII
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 11
e+Jets Analysise+Jets Analysis eejj channel (=1)
Two isolated electron in fiducial regionTwo isolated electron in fiducial region Two jetsTwo jets Remove events in the Z peakRemove events in the Z peak (E(Ett(e(e11)+ E)+ Ett(e(e22)+ E)+ Ett(j(j11)+ E)+ Ett(j(j22) )>450 GeV) )>450 GeV
ejj channel (=0.5) Isolated central electronIsolated central electron Two jetsTwo jets MET >30 GeV, MET >30 GeV, (e,MET)>0.7˚(e,MET)>0.7˚ Mt(eMt(e)>130GeV)>130GeV (E(Ett(e(e11)+ E)+ Ett(e(e22)+ E)+ Ett(j(j11)+ E)+ Ett(j(j22) >330 GeV) >330 GeV
DØ observe 0 events w/ 175 pb-1, expects 0.4±0.1Upper limit at 95%C.L MLQ>238 GeV
DØ observe 2 events w/ 175 pb-1, expects 4.7±0.9Upper limit at 95%C.L MLQ> 194 GeV
First generation LeptoQuarksFirst generation LeptoQuarks
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 12
Jets AnalysisJets Analysis jj channel (=1)
Two muons Two muons 2 jets 2 jets MMJJYY Remove events in the Z peakRemove events in the Z peak (E(Ett(j(j11)+ E)+ Ett(j(j22) ) > 85 GeV) ) > 85 GeV (P(Ptt((11)+ P)+ Ptt((22)) > 85 GeV)) > 85 GeV √ √ j(Ej(Ett ) )22+ + (P(Ptt))22>200 GeV >200 GeV
CDF observe 2 events w/~200 pb-1
CDF expects 3.15±0.17Upper limit at 95%C.LMLQ> 240 GeV (=1)
Second generation LeptoQuarksSecond generation LeptoQuarks
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 13
Jets + Missing Transverse Jets + Missing Transverse EnergyEnergy
jj channel (=0) 2,3 jets (2,3 jets (leading jets in central leading jets in central
regionregion)) MET>60 GeVMET>60 GeV Jets + MET not alignedJets + MET not aligned 80˚ <80˚ <(j,j)<165˚(j,j)<165˚ Veto on leptonsVeto on leptons
Observed 124 events w/ 198pb-1
Expects 118±14 events
Upper limit at 95%C.L 78< MLQ<117GeV
All generation LeptoQuarksAll generation LeptoQuarks
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 14
DØ has done a search Extra Dimensions Graviton is produced recoiling against a jet or Graviton is produced recoiling against a jet or
gluongluon Monojet like topologyMonojet like topology
JJ11 > 150 GeV, > 150 GeV,
JJ22 < 50 GeV, < 50 GeV,
MET > 150GeVMET > 150GeV
(Met,jet)> 30(Met,jet)> 30oo
Observe 63 events; expect 100 Observe 63 events; expect 100 ±6±7±6±7 in 85 pbin 85 pb-1-1
Signal Limit at 95% C.L.=Signal Limit at 95% C.L.= 84 events (expected limit 84 events (expected limit 128 128 ± 28 )± 28 )
Includes large energy scale uncertaintyIncludes large energy scale uncertaintyBoth MC and Data scalesBoth MC and Data scales
Efficiency: 20%Efficiency: 20%
Background: +50% and –30%Background: +50% and –30%
Statistical theory
Jet+Missing Transverse Jet+Missing Transverse EnergyEnergy
Kfactor=1
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 15
ConclusionsConclusions Tevatron is delivering record luminositiesTevatron is delivering record luminosities Detectors have collected ~200 pbDetectors have collected ~200 pb-1-1 of good of good
quality data until September 2003quality data until September 2003 Data analyzed with sensitivity to many modelsData analyzed with sensitivity to many models
Leptoquarks (first, second generations)Leptoquarks (first, second generations) Z’ models (E6, Little Higgs)Z’ models (E6, Little Higgs) Extra Dimension models (ADD, TeV-1, Randall-Extra Dimension models (ADD, TeV-1, Randall-
Sundrum)Sundrum) Excited electronsExcited electrons TechnicolorTechnicolor SUSYSUSY
Stay Tune for more to come from Tevatron Stay Tune for more to come from Tevatron soon!!!soon!!!
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 16
LQ summaryLQ summary
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 17
Tevatron performacesTevatron performacesTevatron successes in early 2004:
Record luminosity 6.8E31 3.9pb-1 integrated in a single
store First store w/ antiprotons from
Recycler
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 18
Dijet High Mass AnalysesDijet High Mass AnalysesL = 75 pb L = 75 pb -1-1
At least 2 jets , |At least 2 jets , ||<2|<2Reduce background: CosReduce background: Cos*<2/3*<2/3
Search for resonances in theinvariant mass of largest Et jetsspectrum. sensible to new physics
Particle 95% C.L. GeV
Axion/Coloron
200<M<1130 200<M<1130
Excited Quark
200<M<760200<M<760
E6 diquark 280<M<420280<M<420
W’ 300<M<410300<M<410
Technirho 260<M<640260<M<640
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 19
Dijet High MassDijet High Mass
With the same With the same invariant massinvariant mass
Search for Randall-Search for Randall-sundrum modelsundrum model
Exclude a region Exclude a region on the Mon the Mgravitongraviton K/MK/Mplpl plane plane
Sensitivity to highK/Mpl and MG mass
Excluded:jj: 220<MG<840 GeV (k/Mpl= 0.3)
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 20
More ee analysisMore ee analysis
ee invariant mass
Acceptance for Spin 1
Acceptance for Spin 0
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 21
More eeMore ee
Searches in dileptons ( Searches in dileptons ( cont’d)cont’d)
Rocío Vilar, IFCA/UC Rencontres de Moriond, March 31st 22
Dielectron eventMee = 371 Gev
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