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Prospects for TeV Scale New Physics at LHC. Reisaburo Tanaka (Okayama University) On behalf of ATLAS-Japan KEK Theory Meeting 2006 March 2-4, 2006. Large cross section via strong interaction Easy discovery M~1TeV within 1 month ?. SUSY Scale 20% accuracy ( L=10fb -1 , mSUGRA )
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Prospects for TeV ScaleNew Physics at LHC Reisaburo Tanaka (Okayama University) On behalf of ATLAS-Japan KEK Theory Meeting 2006 March 2-4, 2006
Large cross section via strong interaction Easy discovery M~1TeV within 1 month ? SUSY Scale 20% accuracy(L=10fb-1, mSUGRA) Missing ET is important (calibrate with Z→ll+jets) Signal 4. Supersymmetry Missing ET+ high pt jets + Leptons (Model indep. Analysis, R-parity conserv.) J.G. Branson et al., Eur.Phys.J.direct C4(2002)N1 Prospects for TeV Scale New Physics at LHC
High PT leptons + multi-jets + b-jets τ-jets Gluino/squark are produced copiously, “Cascade decay” follows after. SUSY event topology (Gravity- mediation + R-parity) High Stop,sbottom ---> ETmiss should be controlled in multi-jets topology (N>=4). High Pt multi-jets are important to estimate SM background contributions and SUSY reconstruction. Prospects for TeV Scale New Physics at LHC
1 month run (L=1fb-1) 〜1.5TeV 5 discovery No EWSB mSUGRA discovery potential High Lum. 3 year run (L=300fb-1) M2.5TeV Cold Dark Matter 1 week run is enough. WMAP 0.0094<Ωmh2<0.129 1 year run (L=10fb-1) M2TeV LEP & Tevatron region Prospects for TeV Scale New Physics at LHC
ME-PS Matching PS(Pythia) 1. Collinear and soft regions are covered with Parton Shower Pythia(6.2). Pt ordering is applied. 2. ME-PS matching is performed to remove double counts: No-Shower branching probability is given by pQCD:Sudakov factorΔ: Two major methods exist: (A) CKKW: Events is reweight with Sudakov factor (product of Δ for all line) (B) MLM: veto is applied after shower evolution PS Prospects for TeV Scale New Physics at LHC F. Krauss et al., Phys.Rev.D70(2004)114009
No lepton mode One Lepton mode S.Asai et al., ATLAS Preliminary Count /400GeV/10fb-1 Effective Mass(GeV) = mET + ΣPT(4jets) (1) One lepton mode gives clean discovery. (2) Top is dominant background. (1) Background increases by factor 2-4 than the PS prediction depending on Meff. (2) Slope becomes more gentle, and similar to the signal <-- important Point Prospects for TeV Scale New Physics at LHC
Tile barrel Tile extended barrel LAr hadronic end-cap (HEC) LAr EM end-cap (EMEC) LAr EM barrel LAr forward calorimeter (FCAL) Lots of materials Crack ||=1.4-1.6 Detector Material ATLAS preliminary T.Sasaki (U.Tokyo) et al. Missing Ex resolution (GeV) Crack +20% worse All eta ∑Et (GeV) Prospects for TeV Scale New Physics at LHC
Bottomup Reconstruction Sharp Edge Mllmax Mass Reconstruction kinematical endpoint B.C. Allanachet al.,JHEP 0009(2000)004 Generally under-constrained. Determine mass with help of models. Can determine model independently if 2-body decay chain continues 3 times. Large tanβ means more cascade and , b. Strong model dependence. Mass uncertainty mostly from LSP’s momentum. Determination of spin or Br are difficult. Prospects for TeV Scale New Physics at LHC
Synergy between LHC and ILC Universal Extra-Dimension scenario Typical mSUGRA scenario Use spin ! H-C.Cheng et al., Phys.Rev.D66(2002)036005, ibid. 056006 B.C.Allanach et al.,Eur.Phys.J.C25(2002)113 squark LHC Higgs neutralino chargino slepton ILC LHC - Higgs, squark/gluino ILC - Higgs, neutralino/chargino, slepton Split supersymmetry: R-hadrons in ATLAS A.C. Kraan et al., hep-ex/0511014 Prospects for TeV Scale New Physics at LHC
Testing the underlying theory • Determination of SUSY model parametres C.G. Lester, M.A. Parker, M.J. White, JHEP 0601(2006)080 • SUSY “inverse map” LHC signatures theoretical models N. Arkani-Hamed et al., hep-ph/0512190 Cross sections Meff Nlepton … Markov chain sampling technique Kinematics Endpoints(mass) Inclusive Signature Exclusive Signature Easy for theory 1808 LHC observables 15 dimensional parametrization Prospects for TeV Scale New Physics at LHC
7. Summary • Discovery first ! • LHC is capable to find new particles (SUSY, ED, Z’ etc. ) up to 2-3 TeV (up to ~10TeV with interference effect). • Model discrimination / parametre determination under study. • Experimental issues: commissioning/calibration • Needs to understand SM bkg from data and tuned MC. • Tools: t, b, W/Z and even Higgs! • We do hope major breakthrough in HEP (SUSY, ED etc.) • Important decision in 2010 about HEP’s future… Prospects for TeV Scale New Physics at LHC