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Update on the MSSM Interpretation of ATLAS Higgs Searches

Update on the MSSM Interpretation of ATLAS Higgs Searches. Markus Schumacher , Bonn University ATLAS Physics Workshop, Athens, May 2003. The Higgs Sector of the MSSM Updated MSSM Scan The 4 Benchmark Scenarios Observation potential for: h, A H, H +-

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Update on the MSSM Interpretation of ATLAS Higgs Searches

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  1. Update on the MSSM Interpretation of ATLAS Higgs Searches Markus Schumacher , Bonn University ATLAS Physics Workshop, Athens, May 2003 • The Higgs Sector of the MSSM • Updated MSSM Scan • The 4 Benchmark Scenarios • Observation potential for: h, A H, H+- • SM versus MSSM if only h seen (1st look) • Conclusion and Outlook

  2. The Higgs Sector of the MSSM • Two Higgs Doublets  5 physical bosons: h, H, A, H+, H- • Parameters of a 2HDM: tanb, a, mh , mH, mA, mH+- • SUSY reduces to tanb, mA at Born level • At Born level: mh < MZ • Large loop corrections  mh < 133 GeV (+-3GeV) corrections depend on 5 SUSY parameters: Xt,M0,M2,Mgluino, m • 5 parameters fixed in4 benchmark scenariosconsidered • Couplings changed w.r.t. to SM • Enhanced BRbb,tt for large tanb Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  3. Updated Interpretation in the MSSM • Most recent calculations for masses a. branching ratios (HDECAY3.0, Feynhiggs1.3  catch up with LEP) • New and updated analysis: e.g. Vector Boson Fusion channels • More and new benchmark scenarios: (same as final LEP paper) • MHMAX Scenario (already in TDR) maximises theoretically allowed region for mh • Nomixing Scenario (already in TDR, with MSUSY= 1 TeV ) • small mh , now use MSUSY= 2 TeV (1TeV excluded by LEP) • 3) Gluophobic scenario • Small a scenario • (see hep/ph0202167 by M.Carena et al. for details) } New!!! Changed phenomenology of h Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  4. The Gluophobic Scenario Coupling of Higgs to gluons gHgg supressed due to Cancellation of top and stop loops (MSUSY=350GeV) very small cross section for gluon fusion reduced sensitivity for Hgg,ZZ 2 gHgg MSSM/SM 1.2<g21.0<g2 <1.20.8<g2 <1.00.6<g2 <0.80.4<g2 <0.60.2<g2 <0.40.0<g2 <0.2 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  5. The Small a Scenario Coupling of Higgs to b-quarks gHbb supressed due to Influence of sbottom and gluino loops (MSUSY=800GeV)  Reduced branching ratio Htt,bb B(hbb) MSSM/SM 1.4<Bbb1.2<Bbb <1.41.0<Bbb <1.20.8< Bbb<1.00.6<Bbb<0.80.4<Bbb <0.60.0<Bbb<0.4 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  6. Mass of the light Higgs boson h 130<Mh 120<Mh<130GeV 110<Mh<120GeV 100<Mh<110GeV 90<Mh<100GeV Mh<90GeV Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  7. Search channels considered • Light CP even Higgs boson (new/updated/TDR) VBF: qqH(htt, hWW, hgg) (low lumi only)ttH(Hbb) , ttH(hWW), bbh(hmm) Hgg (inc.+ass.), HZZ4l,WHlnbb (low lumi only) • Heavy Neutral Higgs bosons: channels above + H/A mm, tt (lep.+had., had.+had. )(low lumi only) H/Att, Hhhbbgg, AZHZhhbbll, WHWWW3l3n, HWWlnln • Charged Higgs bosons: gbtH+- with H+-tb and one tbln ttbWbH+-blnbtnH+-tn and t->bqqttbWbH+-bqqbtn • CAVEAT: we are now entering the (tanb-MA) plane jungle • (discovery = CLB(poisson)<5.7x10-7) • (combination = add significance (>1) in quadrature) • (decay in SUSY particles switched off as in TDR) Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  8. Light Higgs boson h: 30 fb -1 bbhmm VBF, htt VBF,htt+WW tthbb WWhlnbb VBF,hWW VBF channels cover large part of MSSM plane Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  9. Light Higgs boson h: 30 fb -1 bbhmm VBF, htt VBF,htt+WW tthbb WWhlnbb VBF,hWW combined VBF channels cover large part of MSSM plane Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  10. Light Higgs boson h: 10 fb -1 Almost no individual channel observable combination of all channels with signficance > 1 5s discovery 3s observation 5s discovery 3s observation Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  11. Light Higgs boson h: 300 fb-1 For high lumi.: hgg, tthbb hZZ4l contribute All three hgg + tthbb hgg +hZZ4l only tthbb Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  12. h: Number of observable final states 300 fb-1 1 channel 2 channels 3 channels 4 channels 5 channels several channels observable allows parameter determination Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  13. Heavy Neutral Higgs Bosons H/A 4 Scenarios quite similar for H,A,H+- show only MHMAX 30 fb-1 VBF: Htt,WW H/Att ttH(Hbb), ttH(HWW), H/Agg, HZZ4l, WHlnbb, Hhhbbgg, AZHZhhbbll, WHWWW3l3n,HWWlnln Still interesting in general 2HDM Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  14. H/A: Tau Channels added Tau channels New:H/Atthad had Extended: (450 to 800GeV) H/Attlep had 30 fb-1 H/Attlep had H/Attlep had, tthad had H/Atthad had Both combined Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  15. H/A: All Channels H/Amm H/Att combined VBF: Htt,WW 30 fb-1 H/Att ttH(Hbb), ttH(HWW), H/Agg, HZZ4l, WHlnbb, Hhhbbgg, AZHZhhbbll, WHWWW3l3n, HWWlnln Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  16. H/A: 4 Scenarios at 300fb-1 300 fb-1 H/Amm H/Att combined VBF: Htt,WW H/Att ttH(Hbb), ttH(HWW), H/Agg, HZZ4l, WHlnbb, Hhhbbgg, AZHZhhbbll, WHWWW3l3n, HWWlnln Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  17. Charged Higgs Bosons • Two regions: • MH < 170GeV (only low lumi) • ttbWbH+-blnbtn(TDR) • ttbWbH+-bqqbtn(new) b) MH > 180GeV gbtH+,-,H+tb,tbln(TDR) gbtH+,-,H+-tn, tbqq(new) gbtH+,- H+tb,tbln gbtH+,-H+-tn, tbqq ttbWbH+-blnbtn Both new analysis increase coverage (details see Mireia‘s talk) ttbWbH+-bqqbtn Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  18. How many can be seen: h,H,A,H+- ? 300 fb-1 1 boson h,H,A,H+- 2 bosons 3 bosons All 4 bosons h,H,A h only No holes ! Complete plane covered h,H,A Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  19. h,H,A,H+- ? 4 Scenarios Compared 300 fb-1 1 boson 2 bosons 3 bosons All 4 bosons Plane covered in all four benchmark scenarios Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  20. Only h seen: is it the SM or the MSSM ? MHMAX scenario, 300fb-1 From VBF > 1 Higgs boson BR(htt) BR(hWW) R1= From tth BR(hbb) BR(hWW) only h R2= D2=(R1MSSM-R1SM)2/sexp + =(R2MSSM-R2SM)2/sexp D>1 • > 2 Only statistical error Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  21. Conclusion • Updated interpretation of Higgs searches in 4 benchmark scenarios has been performed • Good coverage of MA-tanb plane for all 4 scen., due to complementarity of search channels • New channels for h,H,A,H+- increase sensitivity • Multiple channels observable for light Higgs h  seems to allow some discrimination between SM and MSSM Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  22. Next Steps • Finish study (and write up results obtained so far ?) • Provide „Scan“-Ntuples and Tools • Consider also the case when decay into SUSY particles on • Include systematics and use more sophisticated combination • Consider CP-violating MSSM and general 2HDM • Continue studies on SM  MSSM discrimination • Thanks for discussion and providing info/programs to • M. Spira (HDECAY,HIGLU,…), S. Heinemeyer (FeynHiggs) • T. Plehn (xsec for gbtH+-), Catherine B.+Mireia D. (BR tbH+-)), • especially Elzbieta R.W. and many others from the Higgs group Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  23. Appendix Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  24. h,H,A,H+- ? 4 Scenarios Compared 30 fb-1 1 boson 2 bosons 3 bosons All 4 bosons Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  25. h,H,A,H+- ? 4 Scenarios Compared 30 fb-1 1 boson 2 bosons 3 bosons All 4 bosons For light h channels have been combined Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  26. h,H,A,H+- ? 4 Scenarios Compared 10 fb-1 1 boson 2 bosons 3 bosons All 4 bosons For light h channels have been combined Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  27. H/A: 4 Scenarios at 30fb-1 H/Amm H/Att combined VBF: Htt,WW H/Att ttH(Hbb), ttH(HWW), H/Agg, HZZ4l, WHlnbb, Hhhbbgg, AZHZhhbbll, WHWWW3l3n, HWWlnln Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  28. H/A: 4 Scenarios at 10fb-1 H/Amm H/Att combined VBF: Htt,WW H/Att ttH(Hbb), ttH(HWW), H/Agg, HZZ4l, WHlnbb, Hhhbbgg, AZHZhhbbll, WHWWW3l3n, HWWlnln Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

  29. Charged Higgs boson 30 fb-1 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003

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