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First Look at the Interpretation of ATLAS Higgs Searches in the CPX Scenario of the Complex MSSM

First Look at the Interpretation of ATLAS Higgs Searches in the CPX Scenario of the Complex MSSM. Markus Schumacher , Bonn University May 13th 2004, CERN. Phenomenology of CPX Scenario Technicalities Discovery Potential Problematic Regions ?.

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First Look at the Interpretation of ATLAS Higgs Searches in the CPX Scenario of the Complex MSSM

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  1. First Look at the Interpretation of ATLAS Higgs Searches in the CPX Scenario of the Complex MSSM Markus Schumacher , Bonn University May 13th 2004, CERN • Phenomenology of CPX Scenario • Technicalities • Discovery Potential • Problematic Regions ? Disclaimer: this are first very preliminary results from a study in progress and NOT official ATLAS results. Please do note quote plots as ATLAS results!

  2. The CPX scenario • MSSM Higgs Sector CP conserving at Born level • CP effects via complex couplings in loops: ComplexMSSM relevant for Higgs sector are: complex trilinear couplings At, Ab and complex gluino mass paramer Mgluino Maximal effect in Higgs sector  CPX scenario (suggested by Carena, Ellis, Pilaftsis, Wagner et al.) • Parameter choice for this first scan: MSUSY = 500 GeV, At=Ab=Mgluino=1 TeV, m=2TeV, M2=200GeV, arg(At)=arg(Ab)=arg(Mgluino)=90 degree + scan of Born level parameter: tanb and MH+- M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  3. Phenomenology in the CPX scenario • Mass eigenstates H1, H2, H3 not equal CP eigenstates h,A,H  mixing between CP even and CP odd states • All neutral bosons can couple to pair of W and Z bosons among themselves Hi,Hj,Hk • Compare to CP Conserving real MSSM: no born level coupling of A to WW,ZZ, A to hh (HH) h(H) to Zh(H), A to AZ M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  4. Phenomenology in the CPX scenario • H1, H2 and H3 may • be produced in VBF, WH and ZH processes • decay to pair of W/Zs, pair of Higgs bosons, H+Z bosons Sum rule for couplings: Sigi (ZZHi) = gSM (ZZHSM) H2 and H3 decay into H1H1 and H1Z 3 2 2 H1 H2 H3 M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  5. Mass of the Lightest Higgs Boson H1 120<MH1<130GeV 110<MH1<120GeV 90<MH1<110GeV 70<MH1<90GeV 40<MH1<70GeV 0<MH1<40GeV • even masses between 0 and 40 GeV • not excluded by LEP •  problematic for LHC M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  6. Some Technicalities • masses, couplings and branching ratios calculated so far with FEYNHIGGS 2.1( Heinemeyer, Weiglein et al. ) • needs/will be cross checked by CPSUPERH ( A.Pilaftsis, J.S.Lee et al.) • SM like cross sections calculated in leading order with M. Spira‘s programs + CTEQ5L parton density functions • charged Higgs cross sections obtained from T. Plehn‘s program • MSSM cross sections obtained by appropiate correction factors Gluon fusion: s(MSSM) = G(Hi gg) / G(HSM gg) xs(SM) VBF,ZH,WH: s(MSSM) = gHiVV x s(SM) ttH/bbH: s(MSSM) = sffHix s(ffH) + pffHix s(ffA) 2 2 2 • running bottom quark mass usedd for bbH, gbtH+- • discovery = 5 sigma excess using Poissonian statistics combination of channels with likehood ratio method M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  7. Experimental Inputs • efficiencies and background predictions taken from documented ATLAS analysis (see below) • corrections due to larger total decay width taken into account • for VBF channels: assume same efficiencies for contribution of CP even and CP odd states (needs to be checked) • for ttH: efficiencies for CP even and odd bosons are the same VBF channels: SN-ATLAS-2003-024 ttH, Hbb: ATL-PHYS-2003-003 Charged Higgs: ATL-PHYS-2003-58 (low mass), SN-ATLAS-2002-017, (high mass) bbH/Amm: ATL-PHYS-2002-021 (low mass),ATL-PHYS-2000-005 (high masses) bbH/Att: ttlep. had :ATL-PHYS-2000-001 (low m.), ATL-PHYS-2003-008 (high m.) tthad. Had: ATL-PHYS-2003-008 ( masses > 450 GeV) Remaining analysis from ATLAS Detector and Physics Performance TDR M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  8. Hgg and HZZ4 leptons H1gg, GGF+ass. prod. HiZZ4l 300fb-1 30fb-1 H1 300fb-1 H3 H2 M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  9. ttH with Hbb and bbH with Hmm Zoom in bbH1, H1mm ttH, Hbb H1 300fb-1 H1 300fb-1 H1 30fb-1 H1 30fb-1 H2 300fb-1 discovery region partiallylimited by avaibility of inputs only down to MH = 70 GeV (ttH at low tanb, bbH at low M+-) MH1= 70GeV M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  10. Weak Vector Boson Fusion 30fb-1 Zoom in H1 tt H1 WW H2 tt H3 tt MH2= 110GeV MH1= 110GeV • only studied for low luminosity running so far • (forward jet tagging, central jet • veto in presence of pile up) • discovery region for low tanb • limited by avaibility of inputs • only down to 110 GeV M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  11. Discovery Potential Light Higgs Boson H1 Zoom in MH1= 70GeV bbH1, H1mm • low Higgs masses below 70 GeV not studied yet in ATLAS • for M H+- >190GeV discovery in at least two channels ttH1, H1bb H1ZZ4l H1gg VBF: H1tt M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  12. Discovery Potential H2 and H3 300fb-1 H2WWlnln 140 GeV< MH H2/3  tt30fb-1 H2,3 tt H2/3  mm30fb-1 H2/3  mm300fb-1 H2H1H1bb gg H3H1 Zbb ll H2H1 Zbb ll • tt only studied for low luminosity running so far 60 GeV< MH1, 200<MH2/3 < 360 GeV M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  13. Charged Higgs Bosons high mass: mH+-> mtop gbH+-t H+-tn , tbqq 30fb-1 300fb-1 low mass: mH+-< mtop ttH+- b Wb Wln H+- tn 30fb-1 WqqH+- tn 30fb-1 • only studied for low luminosity running so far • ( tau tagging for soft taus • in presence of pile up) M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  14. Overview of Discovery Potential Zoom in Discovery of H1 Two „problematic“ regions Discovery of H2 and/or H3 Discovery of H+- M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  15. Problematic Region I see what happens if: increased lumi. = 60fb-1 extrapolate inputs to MH=100 GeV VBF, Htt So far:M>110GeV, int. lumi= 30fb-1 H2tt H1tt H2tt H1tt poor man‘s combination of : H1tt andH2tt increased coverage + combination covers hole partially covers hole M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  16. Problematic Region II Analysis surrounding hole: Charged Higgs ttH+- b Wb WqqH+- tn 30fb-1 ttH2, H2bb VBF: H2tt, 30fb-1, 110GeV<MH try look for H3WWlnln MH1<50GeV 100<MH2<110 GeV 130<MH3<180 GeV M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  17. Problematic Region II VBF: H2tt 30fb-1  60fb-1 110GeV<MH  100GeV<MH H3WWlnln 3 s observation with 300fb-1 Charged Higgs 30fb-1  100fb-1 other ideas for improved coverage: investigate high luminosity running for VBF, lower masses for H3ZH1llbb, try ggH+1 hard jet, Htt,mm H+-WH1, Higgs pair production + other new or rare decay modes ?? M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  18. Conclusions • First preliminary interpretation of ATLAS Higgs searches in CPX scenario has been performed • Good coverage over most of tanb vs. MH+-plane, two problematic regions have been identified and ideas for coverage are on the way  study smaller Higgs boson masses at LHC • Investigate „problematic“ regions in more detail  maybe suggest new analysis/ search channels • Crosscheck results with CPSUPERH • Study different values for complex phases Thanks for programs and discussions to: Philip Bechtle, Sven Heinemeyer, Tilman Plehn David Rainwater, Michael Spira,… M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  19. Backup Slides M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  20. Discovery Potential for Heavy Neutrals M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

  21. OPAL PLOTS M. Schumacher, ATLAS Higgs Interpretation in the CPX Scenario of MSSM

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