Searches for heavyresonances Searches and new particles at ATLAS
Sarah Heim, Michigan StateUniversity SarahMichigan Heim, Not reviewed, for internal circulation only on behalf of the ofbehalf on ATLAScollaboration CIPANP 2012 1 For example, it does not it example, For theory,successful thestory... of the end be cannot but a Standard Modelvery Particleis of Physics The cannot be sure of how electroweak sure how symmetrybroken be of is cannot Higgs,we the Also: Beforefind we is weak whyso gravity explain, - a matter dark have candidate - Why are we looking Whywe are forPhysicsbeyond theSM? forces otherfundamental compared the to
Not reviewed, for internal circulation only SarahHeim
2 Searchesresonances for - two gauge bosons gauge - two jets - two photons - two leptons - two talk) states this Final (in analysesare95%alimitsvariety seton C.L. ---> of models the shown anyof excessin significant No found SPOILER: exact of model independently physicscanbe found - new - same statevarious models final canprobe Advantagessignature searches:of
Not reviewed, for internal circulation only ? octetscalars- Color - Excited quarks - Technicolor - RSgraviton bosons - Z'/W' Example models: SarahHeim 3 Searchforresonances dilepton in states final
Not reviewed, for internal circulation only 1.25 TeV1.25 M μμ = = 4 Z boson), not theoretically motivated theoretically not boson), Z as couplings Z' (same Model Standard model: Sequential Benchmark ------Technicolor of the in one mesons technivector - models graviton Sundrum Randall - model) Theory Unified (Grand E6 model inthe boson gauge heavy new - of a signature be could resonances Dilepton Dileptons:Models Kaluza-Klein tower of massive graviton states graviton massive of tower Kaluza-Klein dimension extra warped 1 Z QCD-like spectrum QCD-like Scale Technicolor Low Eichten) model (Lane, E 6 ' E SO 6 = Not reviewed, for internal circulation only Z 10 ' × cos U 1 E6 SU Z ' 5 × sin U 1 E6 × U 1 Sarah Heim k/ M pl = 1.0-0.01 = pl 5 Dileptons:Event selection sign - opposite - impactparameter distancefrom primary and vertex Spectrometercuts Detectorquality - Inner and Muon Muons electronisolated - leading leakage,trackingquality shape, hadronic - shower Electrons p-value: 13%p-value: Resolution(object withp (2 Acceptance TeVZ')
Not reviewed, for internal circulation only T = 1 TeV) 1-2% ~70% Electrons p-value: 82% 10-25% ~45% Muons q q/g /g ? ~5 fb ~5 6 l l - + -1
Dileptons:Limits or E6GUT) Standard Model (Sequential Z' boson gauge 1:new Spin
RS gravitonRS (k/ StandardSequential Model Z'
95% C.L. lower mass limits on reference models: limits reference mass on 95% C.L. lower
Not reviewed, for internal circulation only M Pl = 0.1)= 2.16 2.21 Observed[TeV]dilepton limit (different width, acceptance)width, (different 2: RSgravitons Spin ATLAS-CONF-2012-007 SarahHeim
~5 fb ~5 7 -1
Dileptons:Technicolor Limits
ρ T / ω T
(m( Not reviewed, for internal circulation only 95% C.L. limits on reference model: 95% C.L. limitson reference ρ T /ω T )-m( π T ) = 100=) GeV) 0.47 Observed[TeV] dilepton limit (Phys.Rev. Lett.106 (2011) 171801 excess CDFWjj of interpretation Scale technicolor Low
ATLAS-CONF-2011-125 SarahHeim ~1 fb ~1 8 -1 )
- limits (k/ - limits twice dielectron/dimuon ~ fraction branching - diphoton RS graviton: Dileptons anddiphotons
M Pl = 0.1)[TeV]: = 1.95 (diphoton+dilepton) 1.85 (diphoton),
Not reviewed, for internal circulation only PLB 710 (2012) PLB710 ~1-2 fb ~1-2 9 -1 Searches in dijet final states states final Searches in dijet
Not reviewed, for internal circulation only 10 interaction contact - Quark holes black - Quantum distributions spectrum/angular in mass Deviation scalars octet - Color quarks - Excited Resonances Dijets: Models Dijets: - interference with QCD (here: destructive) destructive) (here: QCD with - interference scale compositeness above (visible compositeness - quark production for relativity classical - assume (M dimensions - extra gluons two into decaying resonance - colored composite are if quarks - possible
Not reviewed, for internal circulation only Pl reduces to M to reduces D ) q/g q /g becomes strong Scaleat which gravity ? q/g q /g Λ ) 11 |y*| system- centermass of in | - k leastjets (anti twoat with events - search in also - and quality fit check - spectruma dijetmass fit with - Dijets: Event SelectionDijets: angular distributions excesses search for peak-like background estimate to SM function than SMdijet production) more be isotropic to expected (jets are from new smallbe physics must y | < 2.8, p 2.8, | <
Not reviewed, for internal circulation only T > 80 GeV 80 > T , R= 0.6) q q/g /g ? ~5 fb ~5 12 q/g q -1 /g
Quark contact interaction Quantum Mini (n Holes 6)= Black Color octet scalars s8 Color s8 octet scalars quarksq* Excited Dijets: Limits Dijets:
Not reviewed, for internal circulation only 95% C.L. limits on reference models: 95% C.L. limitson reference Compositenessscale Gravity scale mass mass Limit on Observed [TeV] limit 7.8 4.11 1.94 3.35 ATLAS-CONF-2012-038 ~5 fb ~5 13 -1 Searchforresonances diboson in states final
Not reviewed, for internal circulation only 14 limit also - fiducial on (k/ RS graviton - kT,(anti jet pair electrons/muons, 0.4) R = isolated two lljj:exactly electrons/muons isolated llll:2of pairs (inv.Z mass) to close of pairs masses channels 2 physics (llll) physics ZZ any new for set section cross GeV for 325-845 excluded ZZ
Not reviewed, for internal circulation only M Pl = 0.1) = 0.1) arXiv:1203.0718 to SubmittedPLB ~1 fb ~1 15 -1 WZ charged, oppositely two ---> ee, Z-> - m(a - m(a - (m( on Limits GeV 760 Model: Gauge in extended limit mass W' on Lower variable: discriminating - excluded m( excluded m( excluded ρ exactly one additional lepton, MET MET lepton, additional one exactly leptons, same flavor T T T )-m( ) >> m( >> ) = 1.1 ) μμ and μμ and π
ρ Not reviewed, for internal circulation only T T ) = m(W)) ) = in Low Scale Scale Technicolor in Low ρ T ρ ρ ) T T W-> ) < 469 GeV 469 < ) GeV 483 < ) νe, νμ νe, arXiv:1204:1648 PRD to Submitted ~1 fb ~1 16 -1 Conclusions image of ATLAS detector Simulated black hole event superimposed over searches - resonance forward results! 2012 Looking to ranges for models exclusion many - extended far so found physics new - no final states variety of a in resonanceresults ofsearchesat Presented ATLAS higher CMhigher energy directly from benefit
Not reviewed, for internal circulation only SarahHeim 17 Backup:WZ Limits check as acceptance use W' ---> affects acceptance, correlations spin modeled without template - signal -scenarios: considertwom sin( - assume m( on - depend on Limits and
Not reviewed, for internal circulation only π T mixing with EW bosons gauge with mixing ρ T in Low Technicolor Scale in Model χ ) = 1/3 ) π T ) andm (a T ), (a T ) = 1.1 m( = 1.1 ) ρ T ), m ), (a SarahHeim T ) m( >> ~1 fb ~1 ρ T 18 ) -1 Predictedlimits - depends on the achieved acceptance achieved on the depends -
Not reviewed, for internal circulation only Sarah Heim 19