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. 2 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 The Higgs Sector of the MSSM Two Higgs Doublets  5 physical bosons: h, H, A, H +, H - Parameters of a 2HDM: tanm h, m H, m A, m H+- SUSY reduces to tan, m A at Born level At Born level: m h < M Z Large loop corrections  m h < 133 GeV (+-3GeV) corrections depend on 5 SUSY parameters: X t,M 0,M 2, M gluino,  5 parameters fixed in 4 benchmark scenarios considered MSSM /SM t b/ W/Z h cos sin -sin cos sin() H sin sin cos cos cos() A cottan ----- Couplings changed w.r.t. to SM  Enhanced BR  bb, for large tan

3. 3 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 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 ) 1)MHMAX Scenario (already in TDR) maximises theoretically allowed region for m h 2)Nomixing Scenario (already in TDR, with M SUSY = 1 TeV ) small m h, now use M SUSY = 2 TeV (1TeV excluded by LEP) 3) Gluophobic scenario 4)Small scenario (see hep/ph0202167 by M.Carena et al. for details) } New!!! Changed phenomenology of h

4. 4 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 The Gluophobic Scenario Coupling of Higgs to gluons g Hgg supressed due to Cancellation of top and stop loops (M SUSY =350GeV)  very small cross section for gluon fusion reduced sensitivity for H  ,ZZ g Hgg MSSM/SM 2 1.2<g 2 1.0<g 2 <1.2 0.8<g 2 <1.0 0.6<g 2 <0.8 0.4<g 2 <0.6 0.2<g 2 <0.4 0.0<g 2 <0.2

5. 5 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 The Small  Scenario Coupling of Higgs to b-quarks g Hbb supressed due to Influence of sbottom and gluino loops ( M SUSY =800GeV )  Reduced branching ratio H  ,bb B(h  bb) MSSM/SM 1.4<B bb 1.2<B bb <1.4 1.0<B bb <1.2 0.8< B bb <1.0 0.6<B bb <0.8 0.4<B bb <0.6 0.0<B bb <0.4

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

7. 7 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 Search channels considered Light CP even Higgs boson ( new/updated/TDR ) VBF: qqH(h  , h  WW, h  ) (low lumi only) ttH(H  bb), ttH(h  WW), bbh(h  ) H   (inc.+ass.), H  ZZ  4l,WH  lbb (low lumi only) Heavy Neutral Higgs bosons: channels above + H/A  , (lep.+had., had.+had. ) (low lumi only) H/A  tt, H  hh  bb, A  ZH  Zhh  bbll, WH  WWW  3l3, H  WW  ll Charged Higgs bosons: gb  tH +- with H +-  tb and one t  bl tt  bWbH +-  blb H +-   and t->bqq tt  bWbH +-  bqqb CAVEAT: we are now entering the (tan-M A ) plane jungle (discovery = CLB(poisson)<5.7x10 -7 ) (combination = add significance (>1) in quadrature) (decay in SUSY particles switched off as in TDR)

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

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

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

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

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

13. 13 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 Heavy Neutral Higgs Bosons H/A VBF: H  ,WW H/A  tt ttH(H  bb), ttH(H  WW), H/A  , H  ZZ  4l, WH  lbb, H  hh  bb, A  ZH  Zhh  bbll, WH  WWW  3l3,H  WW  ll 4 Scenarios quite similar for H,A,H +-  show only MHMAX Still interesting in general 2HDM 30 fb -1

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

15. 15 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 H/A: All Channels VBF: H  ,WW H/A  tt H/A   combined H/A   ttH(H  bb), ttH(H  WW), H/A  , H  ZZ  4l, WH  lbb, H  hh  bb, A  ZH  Zhh  bbll, WH  WWW  3l3, H  WW  ll 30 fb -1

16. 16 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 H/A: 4 Scenarios at 300fb -1 VBF: H  ,WW H/A  tt H/A   ttH(H  bb), ttH(H  WW), H/A  , H  ZZ  4l, WH  lbb, H  hh  bb, A  ZH  Zhh  bbll, WH  WWW  3l3, H  WW  ll H/A   combined 300 fb -1

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

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

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

20. 20 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 Only h seen: is it the SM or the MSSM ? only h > 1 Higgs boson MHMAX scenario, 300fb -1 BR(h  ) BR(h  WW) BR(h  bb) BR(h  WW) R1= R2= From VBF From tth  2 =(R1 MSSM -R1 SM ) 2  exp =(R2 MSSM -R2 SM ) 2  exp > 2 >1 Only statistical error

21. 21 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 Conclusion  Updated interpretation of Higgs searches in 4 benchmark scenarios has been performed  Good coverage of M A -tan 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

22. 22 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 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

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

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

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

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

27. 27 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 H/A: 4 Scenarios at 30fb -1 VBF: H  ,WW H/A  tt H/A   ttH(H  bb), ttH(H  WW), H/A  , H  ZZ  4l, WH  lbb, H  hh  bb, A  ZH  Zhh  bbll, WH  WWW  3l3, H  WW  ll H/A   combined

28. 28 Markus Schumacher, Universität Bonn ATLAS Physics Workshop, Athens, May 2003 H/A: 4 Scenarios at 10fb -1 VBF: H  ,WW H/A  tt H/A   ttH(H  bb), ttH(H  WW), H/A  , H  ZZ  4l, WH  lbb, H  hh  bb, A  ZH  Zhh  bbll, WH  WWW  3l3, H  WW  ll H/A   combined

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