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  • :

    I. ( ) ADD? A) B) C) D)

    II. : A) B) C) D)

    III. ADD A) B) 1/, .. , C) , ( ) D) (

  • : . , 4:

    :

    LHC

    ( )

    ,

    ED

  • LHC

  • , LHC

  • ATLAS and CMS ExperimentsTotal weight 7000 tOverall Diameter 25 mBarrel toroid length 26 mEnd-cap end-wall chamber span 46 mTotal weight 12 500 tOverall diameter 15.00 mOverall length 21.6 mMagnetic filed 4 TeslaLarge general-purpose particle physics detectorsDetector subsystems are designed to measure:the energy and momentum of photons, electrons, muons, jets, missing ET

  • , ECAL , HCAL , HF 6 , 13 - 14500 - 14,60 , - 21,60 , - 4 - CMS

  • CMS SX5

    UX5 US5 LHC

  • CMS

  • -

  • SM Fundamental Particle Appears As (ECAL shower, no track)e e (ECAL shower, with track) (ionization only)g Jet in ECAL+ HCALq = u, d, s Jet (narrow) in ECAL+HCALq = c, b Jet (narrow) + Decay Vertex t W +b W + be Et missing in ECAL+HCAL l + +l Et missing + charged leptonW l + l Et missing + charged lepton, Et~M/2Z l+ + l- charged lepton pair l + l Et missing in ECAL+HCAL

  • CMS

  • LHC? , (- , , )

    ( , , , ).

    ,

    ,

    , , ( )

    ( , , - -)

  • Experimental Signals Di-lepton, di-jets and di-photon resonance states (new particles) in RS1-model (RS1-graviton) and TeV-1 extra dimension model (ZKK)

    Di-leptons, di-jets continuum modifications (virtual graviton production in ADD)

    Single Jets/Single Photons + Missing ET (direct graviton production in ADD)

    Single Leptons + missing ET in WKK decays in TeV-1 extra dimension model (WKK)

    Back-to-back energetic jets + Missing ET (UED)

    4 jets + 4 leptons + Missing ET (mUED)

  • Experimental UncertaintiesEnergy MisCalibration performance of e//hadron energy reconstruction.

    Misalignment effect increase of the mass residuals by around 30%

    Drift time and drift velocities

    Magnetic and gravitational field effects can cause a scale shift in a mass resolution by 5-10%

    Pile-up mass residuals increase by around 0.10.2 %

    Background uncertainties (variations of the bg. shape) a drop of about 10-15% in the significance values

    Trigger and reconstruction acceptance uncertainties

  • Some theoretical uncertainties

    QCD and EW high-order corrections (K factors)

    Parton Distribution Functions (PDF)

    Hard process scale (Q2)

    Cut efficiency, significance estimators..

  • , PDF

    PDF .

    PDF , +-7% Mll>1

    - . ( , , PDF). x Q2, .

    10-15 % 3 , .(n=3 ADD c 7.5 6.5 ).

    STEQ6M: x=10-3 10-4, 2.6 (6) % u(d) x=0.6-0.7 100%

  • ADD scenario flat bulk space, large extra dimensions, d=2-6. Arkani-Hamed et el., Phys. Lett. B 429, 263 (1998), I. Antoniadis et al., Phys Lett. B 436, 257 (1998) Infinite tower of KK graviton excitations G(K) with m2 k2/R2 (very light) and spin 2

    Interaction of an individual state G(K) with SM fields is strongly suppressed by 1/MPl . But: Our world is (4+d) dimensional

    SM fields live on the 4D-brane while gravity can propagate in n flat extra compactified dimensions Large multiplicity due to small mass splitting (~ 10-3 eV) enhances interactionsis enough for experimental observation

  • K. Cheung and G. Landsberg, PRD62T. Ham, J.D. Lykken, R.-J.Zhang, PRD59 ADD

  • Virtual graviton productionADD Discovery limit1 fb-1: 3.9-5.5 V for n=6..310 fb-1: 4.8-7.2 V for n=6..3100 fb-1: 5.7-8.3 V for n=6..3300 fb-1: 5.9-8.8 V for n=6..3I. Belotelov et al. CMS NOTE 2006/076CMS PTDR 2006Confidence limits for two muons in the final state

    PYTHIA + CTEQ6L, LO + K=1.30

    Full (GEANT-4) simulation/reco + L1 + HLT(riger)

    Theoretical uncert.

    Misalignment, trigger and off-line reco inefficiency, acceptance due to PDF

  • Real graviton productions=14 TeVL=100 fb-1ETmiss (GeV)jW(e/ )jW()jZ()Tot back=2 MD=4 TeV=2 MD=8 TeV=3 MD=5 TeV=4 MD=5 TeVADD Discovery limit jet + G jet + high missing ET

    Bckgr.: Z/W + jet jet + + /jet + l +

    ISAJET with CTEQ3L

    Fast simulation/recoMD= 7.7, 6.2, 5.2 TeVfor n = 2,3,4MD= 1 1.5 TeV for 1 fb-1 2- 2.5 TeV for 10 fb-1 3- 3.5 TeV for 60 fb-1

  • RS1 ModelModel Parameters:Curvature: k (~M)Compactification radius: rCoupling constant: c = k/MlGravity scale : =Mle-krL.Randall, R.Sundrum (RS scenario), PRL83 3370 (1999) 5D curved space with AdS metric: Signals:Narrow, high-mass resonances states in di-leptons, di-jets, di-photons events:

  • RS1 Discovery Limit two muons/electrons in the final state

    Bckg: Drell-Yan/ZZ/WW/ZW/ttbar

    PYTHIA/CTEQ6L

    LO + K=1.30 both for signal and DY

    Full (GEANT-4) and fast simulation/reco

    Viable L1 + HLT(riger) cuts

    Theoretical uncert.

    Misalignment, trigger and off-line reco inefficiency, pile-up Di-lepton statesI. Belotelov et al. CMS NOTE 2006/104CMS PTDR 2006B. Clerbaux et al. CMS NOTE 2006/083CMS PTDR 2006G1+-G1e+e-c=0.1100 fb-1c=0.01100 fb-1

  • Bckg: QCD hadronic jets

    L1 + HLT(riger) cutsRS1 Discovery Limit two photons in the final state

    Bckg: prompt di-photons, QCD hadronic jets and gamma+jet events, Drell-Yan e+e-

    PYTHIA/CTEQ5L

    LO for signal, LO + K-factors for bckg.

    Fast simulation/reco + a few points with full GEANT-4 MC

    Viable L1 + HLT(riger) cuts

    Theoretical uncert.

    Preselection inefficiencyDi-photon statesG1Di-jet states5 Discovered Mass: 0.7-0.8 TeV/c2c=0.1

  • TeV-1 Extra Dimension Model

    I. Antoniadis, 1991 Multi-dimensional space with orbifolding (5D in the simplest case, n=1)

    The fundamental scale is not planckian: MS ~ TeV

    Gauge bosons can travel in the bulk

    Fermion-gauge boson couplings can be exponentially suppressed for higher KK-modes

    Fundamental fermions can be localized at the same (M1) or opposite (M2) points of orbifold destructive or constructive interference with SM modelppZ1/1e+e-G. Azuelos, G. Polesello EPJ Direct 10.1140 (2004)

  • 5 discovery limit of(M1 model)ATLAS expectations for e and :PYTHIA + Fast simu/reco + Theor. uncert.R-1 = 5.8 TeV @100 fb-1B. Clerbaux et al. CMS NOTE 2006/083CMS PTDR 2006Di-electron states (ZKK decays)TeV-1 ED Discovery Limits two electrons in the final state

    Bckg: Drell-Yan/ZZ/WW/ ZW/ttabr

    PYTHIA/PHOTOS with CTEQ61M

    LO + K=1.30 for signals, LO + K-factors for bckg.

    Full (GEANT-4) simulation/reco

    L1 + HLT(riger) cuts Theoretical uncert.

    Low luminosities pile-up

  • Spin-1 States: Z from extended gauge models, ZKKSpin-2 States: RS1-graviton Spin-1/Spin-2 DiscriminationI. Belotelov et al. CMS NOTE 2006/104CMS PTDR 2006Z vs RS1-graviton

  • LHC Start-up Expectations

  • ConclusionsATLAS and CMS analyses cover a large part of different hypotheses proposed tosolve a number of problems of Standard Model

    The discovery potential of both experiments makes it possible to investigate if extradimensions really exist within various ED scenarios at a few TeV scale: Large Extra-Dimensions (ADD model) Randall-Sundrum (RS1) TeV-1 Extra dimension Model Universal Extra Dimensions

    The performance of detector systems allows to perform searches in the differentchannels A proper energy, momentum angular reconstruction for high-energy leptons and jets, Et measurement b-tagging An identification of prompt photons

    New results are expected at the start-up LHC weeks (integrated luminosity < 1 fb-1)

    Many analyses are out of this talk: Black Holes, Bulk Scalars, Singlet Neutrino etc.

    RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004 RDMS CMS Collaboration Conference, Minsk, November 29, 2004