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Higgs at LHC Introduction Updated results on SM Measurement of Higgs Boson parameters

Higgs at LHC Introduction Updated results on SM Measurement of Higgs Boson parameters MSSM Other exotica. Louis Fayard LAL-Orsay. A non exhaustive review. See later specific talks on Higgs at LHC here by C.Broutin S.Gascon J-F.Marchand.

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Higgs at LHC Introduction Updated results on SM Measurement of Higgs Boson parameters

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  1. Higgs at LHC Introduction Updated results on SM Measurement of Higgs Boson parameters MSSM Other exotica Louis Fayard LAL-Orsay A non exhaustive review See later specific talks on Higgs at LHC here by C.Broutin S.Gascon J-F.Marchand L.Fayard 31-3-2009

  2. I apologize to people who were at Split, because my talk will be very similar But Split was only few days after the accident of September 19th and we now have a better idea of the future .. Probably  L dt < 0.3 fb-1 at  s < 10 TeV L.Fayard 31-3-2009

  3. This delay was used in order to understand the detectors dE/dx in CMS calorimeter A.Ledovskoy @ TIPP09 L.Fayard 31-3-2009

  4. We will not answer all what interest theorists Disclaimer C.Quigg Rept.Prog.Phys.70:1019-1054,2007 I will speak almost only about  s = 14 TeV but I may (try to) answer some questions L.Fayard 31-3-2009

  5. Brout Englert Higgs …. 1964 A lot of things (even important like trigger and description of data driven background estimation) are missing in this talk ! 1984 Lausanne 1992 1994 1999 2006 2008 2009 LHC experiments LOI ATLAS and CMS TP ATLAS Physics TDR CERN/LHCC/99-14 CERN/LHCC/99-15 CMS Physics TDR CERN/LHCC 2006-001 CERN/LHCC 2006-021 J. Phys. G: Nucl. Part. Phys. 34 (2007) 995–1579 ATLAS Expected Performance arXiv:0901.0512+ additional CMS notes Increasing complexity of the analysis ( that should be more realistic ) L.Fayard 31-3-2009

  6. SM Higgs A.Djouadi Phys.Rept.457:1-216 Width smaller than ‘leptonic/ resolution’ Favored by LEP mH = 90 +36-27 GeVmH < 163 GeV , 191 GeV 95% CL L.Fayard 31-3-2009 LEP,TeVatron,SLD B.Kehoe @ Moriond QCD 2009 including direct LEP limit

  7. Direct limit from TeVatron arXiv:0903.4001 Use of TeVatron Likelihood J.Stelzer , G.Salam @ Moriond QCD 2009 http://gfitter.cern.ch L.Fayard 31-3-2009

  8. A.Djouadi Phys.Rept.457:1-216 GF H → WW, ZZ , γγ VBF H → WW , γγ ,  Typical uncertainties on cross-section gg 10 % NNnLO VBF 5% NLO WH,ZH 5% NNLO ttH 15% NLO H → WW, γγ These production cross sections have to be used with the decaysbb ,  , WW , ZZ ,  H → WW, γγ, bb L.Fayard 31-3-2009

  9. H general search ATLAS EP J-F.Marchand CMS TDR S.Gascon M.Pieri et al. CMS note 2006/112 M.Dubinin et al. CMS note 2006/097 M.Lethuillier et al. CMS note 2006/110 ttH Inclusive analysis VBF analysis WH ZH Important reducible background need good /jet separation Good mass reconstruction important need vertex reconstruction If vertex unknown add 1.4 GeV to mass resolution Calo pointing in ATLAS gives vertex resolution of 1.7 cm while (beam) = 5.6 cm A large amount of material in the Inner Detector in front of the em calorimeter  importance of conversions L.Fayard 31-3-2009 ATLAS JINST 3:S08003,2008

  10. H+ETmiss+ 1l S/B  2 ttH WH inclusive S/B  .03 H+1j S/B  .08 VBF + more jets with gg H H+2j S/B  .4 VBF mainly H+ETmiss S/B  2 ZH WH For different final states different S/B L.Fayard 31-3-2009

  11. ATLAS : combined fit using variables ( pT , jets , cos*) and categories ( , conversions ) CMS optimized : NN with kinematics as input , using categories (  , cluster shape  conversion info) small differences  understood L.Fayard 31-3-2009

  12. Evolution of ATLAS background since TDR ( multiplied by 2.3 ) several reasons : ► For irreducible (  ) background now take into account NLO computation (DIPHOX,RESBOS) ► K factors (for j and jj ) different ► It was realised that the rejection of gluons is ( about 10 times ) larger than the rejection of quarks and also that the rejection of quarks in jj is ( < 2 times ) larger than the rejection of quarks in j ► There is more matter in the Inner Detector now Differences between ATLAS and CMS ► different isolation cuts ► different simulations of the irreducible background ( larger pT in ATLAS because use of NLO MC ) and of reducible background (possible jet correlations taken into account in CMS while ATLAS is using parametrisations ) ► different EM calorimeter mass resolutions ► different ID magnetic field 4T(CMS) 2T (ATLAS) ► different granularities of EM calorimeter (longitudinal :  pointing in ATLAS, transversal (1st compartment) 0 rejection easier in ATLAS) L.Fayard 31-3-2009

  13. ee 4 4e H 4l ATLAS EP CMS TDR D.Futyan,D.Fortin and D.Giordano CMS note 2006/136 M.Aldaya et al. CMS note 2006/106 S.Abdullin et al. Acta Phys.Pol.B38(2007) 731-738 S.Baffioni et al. CMS note 2006/115 CMS PAS HIG-08-003C.Broutin ee 4 4e ee 4 4e Main backgrounds : ZZ (irreducible) , tt and Zbb (reducible) + fakes Tools for background suppression : lepton isolation and impact parameter there are 4 leptons be careful about efficiency L.Fayard 31-3-2009

  14. CMS PAS HIG-08-003C.Broutin the detector simulation was done using calibration and alignment conditions representing our anticipated knowledge after the first 100pb-1 of integrated luminosity L.Fayard 31-3-2009

  15.   lh VBF H    ll,lh,hh ATLAS EP CMS TDR C.Foudas,A.Nikitenko and M.Takahashi CMS note 2006/088 CMS PAS HIG-08-008 2 high pT tag jets at large rapidity no color flow between tag jets  rapidity gap central jet veto effective to reduce backgrounds reconstruction of Higgs mass with collinear approximation and angle between the two  L.Fayard 31-3-2009

  16. CMS similar in CMS , slightly tighter cuts (pile-up included L = 2 1033 cm-2 s-1 ) L.Fayard 31-3-2009

  17. CMS PAS HIG-08-008 L.Fayard 31-3-2009

  18. WW(e) incl VBF  WH (3l) ttH H WW H WW  lνlν ATLAS EP CMS TDR V.Drollinger et al. CMS note 2006/055 F.Beaudette et al. CMS note 2006/114 G.Davatz,M.Dittmar and A.Giolo-Nicollerat CMS note 2006/047 J.Phys.G33:N85,2007 CMS PAS HIG-08-006 C.Broutin C.Delaere CMS note 2006/053 H.Pi et al. CMS note 2006/092 E.Yazgan et al. CMS note 2007/011 WH (3l) VBF WW  lνjj VBF WW lνlν correlation in  between 2 leptons no mass peak  need precise knowledge of background  develop data driven methods CMS TDR L.Fayard 31-3-2009

  19. CMS PAS HIG-08-006 ATLAS EP • Floating mass fit • Some look-elsewhere effect taken into account Reasonable (?) agreement (t tbar background smaller in ATLAS ) However discrepencies remain in H+2j analysis L.Fayard 31-3-2009

  20. ttH, H bb semileptonic top decay ATLAS EP CMS TDR S.Cucciarelli,A.Schmidt,C.Weiser, C.Riccardi,P.Torre, D.Benedetti,A.Santocchia,C.Hill, J.Incandela and S.Koay CMS note 2006/119 J.Phys.G:Nucl.Part.Phys. 34 (2007) N221-N250 semileptonic , dileptonic and all hadronic channels Very difficult large background , similar to signal CMS 60 fb-1 L.Fayard 31-3-2009

  21. General Higgs significances CMS TDR L.Fayard 31-3-2009

  22. ATLAS EP 5  L.Fayard 31-3-2009

  23. Is it a Standard Model Higgs ? D.Rainwater hep-ph/0702124 Very (!) difficult pp → HH → WWWW ► limited H mass range at least sLHC luminosities needed ► analysis (same sign dileptons + 4 jets has to be reassessed in a more realistic way L.Fayard 31-3-2009

  24. Direct mass and width measurement ATLAS 300 fb-1 statistical precision on Higgs mass measurement (  not limited by systematic uncertainties) ATLAS and CMS TDR L.Fayard 31-3-2009

  25. Spin and CP measurement ► angular distributions in H→ZZ→ 4l± ► jet distributions in vector boson fusion Not for early data … needs to find Higgs first ! Remember that if H   cannot be spin 1 (Landau-Yang’s theorem) L.Fayard 31-3-2009

  26. angular distributions in H→ZZ→ 4l± 3 Observables J.R. Dell'Aquila and C.A. Nelson Phys.Rev.D33:101,1986 S.Choi,D.Miller,M.Muhlleitner and P.Zerwas Phys.Lett.B553:61-71,2003 C.P.Buszello,I.Fleck,P.Marquard and J.J. van der Bij Eur Phys J C32,209,2004 CMS TDR - M.Bluj CMS NOTE 2006/094 R.Godbole,D.Miller and M.Muhlleitner JHEP 0712:031,2007 L.Fayard 31-3-2009

  27. Spin 0 CP couplings pseudoscalar scalar The minimal value of the factor C2 needed to exclude the scalar (left) and the pseudoscalar (right) Higgs boson at “N sigmas” level (N=1, 3) as a function of the parameter ξ (pseudoscalar =CP odd part) CMS TDR - M.Bluj CMS NOTE 2006/094 L.Fayard 31-3-2009

  28. Anomalous Higgs Couplings in VBF fusion T.Plehn,D.Rainwater and D.Zeppenfeld Phys Rev Lett 88,051801,2002 T.Figy and D.Zeppenfeld Physics Letters B 591 (2004) 297-303 V.Hankele,G.Klamke,D.Zeppenfeld and T.Figy Phys.Rev.D74:095001,2006 C.Ruwiedel,M.Schumacher and N.Wermes Eur.Phys.J.C51:385-414,2007 statistics in this plot is infinite With 10 fb-1 can exclude CPE and CPO anomalous couplings at 5 sigmas in WW→ llνν for mH=160 GeV and with 30 fb-1 at 2 sigmas in  for mH=120 GeV Additional results for SM + CPE L.Fayard 31-3-2009

  29. M.Duhrssen ATL-PHYS-2003-030 M.Duhrssen,S.Heinemeyer,H.Logan,D.Rainwater,G.Weiglein and D.Zeppenfeld Phys Rev D70,113009,2004 Higgs couplings based on ‘old’ expectations , in particular H  bb Measure .BR in different channels with almost no assumptions (uncertainties = selection efficiencies , background) L.Fayard 31-3-2009

  30. M.Duhrssen ATL-PHYS-2003-030 assuming mainly no new particles in loop … one can express rates and BR as a function of 5 couplings gW, gZ, gt, gb, g One can also do other analysis with stricter assumptions L.Fayard 31-3-2009

  31. MSSM couplings to down part of doublets ( b ,  ,  ) enhanced at high tan(β) 5 Higgs bosons ( 3 neutrals and 2 charged ) D.Rainwater hep-ph/0702124 MSSM at LO MSSM Higgs sector depends of 2 parameters MA tan() at NLO more SUSY parameters  choose a benchmark scenario mhmax corresponds to maximal theoretically allowed region for mh L.Fayard 31-3-2009

  32. Search for neutral MSSM Higgs Associated production with b L.Fayard 31-3-2009

  33. CMS TDR J.Fernandez CMS NOTE 2006-080 Very Difficult 60 fb-1 60 fb-1 Ask for  3 b jets 2 L.Fayard 31-3-2009

  34. μ+μ- CMS TDR ATLAS EP Background rejection - muon isolation - b tagging - reject large missing ET - jet vetos backgrounds L.Fayard 31-3-2009

  35. MSSM Higgs  excellent dimuon mass resolution of ATLAS and CMS is a key point in this analysis There is also a hard b-tag analysis 0 b-jet  1 b-jet  1 b jet 0 b jet L.Fayard 31-3-2009

  36. MSSM Higgs  Differences not understood CMS Physics TDR ATLAS EP 5  One can measure the width and then « measure » tan() L.Fayard 31-3-2009

  37. CMS TDR S.Lehti CMS NOTE 2006/101 ATLAS EP e e , ee , μμ +-  dileptons Cuts on missing ET (ATLAS), b momentum , lepton momentum number of jets ( =1 for CMS) to reject Z and tt backgrounds tighter cuts for CMS mass can be reconstructed similar to VBF  L.Fayard 31-3-2009

  38. CMS TDR S.Lehti CMS NOTE 2006/101 ATLAS EP e e , ee , μμ +-  dileptons 5  L.Fayard 31-3-2009

  39. +-   hadrons  e hadrons  hadronshadrons Zee Z tt Wt W jets dominant background  data driven estimation tt and Z  +  jet CMS TDR A.Kalinowski,M.Konecki and D.Kotlinski CMS NOTE 2006/105 R.Kinnunen and S.Lehti CMS note 2006/075 S.Gennai,A.Nikitenko and L.Wendland CMS NOTE 2006/126 L.Fayard 31-3-2009

  40. Search for charged MSSM Higgs High mass charged Higgs m(H+) > m(top) Low mass charged Higgs m(H+) < m(top) AC AC A AC A ATLAS EP CMS TDR M.Baarmand,M.Hashemi and A.Nikitenko J. Phys. G32 (2006) N21-N40 S.Lowette,J.D'Hondt,P.Vanlaer CMS-NOTE-2006-109 R.Kinnunen CMS-NOTE-2006-100 L.Fayard 31-3-2009

  41. General discovery sensitivity on H+ ATLAS EP M.Hashemi,S.Heinemeyer,R.Kinnunen,A.Nikitenko and G.Weiglein arXiv:0804.1228 [hep-ph] L.Fayard 31-3-2009

  42. General 5  discovery regions in MSSM (mhmax scenario) CMS TDR everything is covered L.Fayard 31-3-2009

  43. MSSM charged Higgs decays g b →t H+(→ χi0χj+ ) → 3 l± M.Bisset,F.Moortgat and S.Moretti Eur.Phys.J.C30:419-434,2003 C.Hansen,N.Gollub,K.Assamagan and T.Ekelof Eur.Phys.J. C44, s2.1-s2.9 (2005) MSSM Higgs decays H,A → χi0χj0 , χi+χj- → 4 l±+ MET M.Bisset,J.Li,N.Kersting,F.Moortgat and S.Moretti arXiv:0709.1029 CMS Physics TDR C.Charlot,R.Salerno and Y.Sirois CMS-NOTE-2006-125 ATLAS presented at Charged-Higgs-08 Search for A → Z (→l+l-) h(→ bb) CMS Physics TDR G.Anagnostou and G.Daskalakis CMS-NOTE-2006-063 I will not discuss NMSSM Higgs I.Rottlaender and M.Schumacher ATL-PHYS-CONF-2008-009 Updated MSSM scan for different benchmark scenarios M.Schumacher hep-ph/0410112 CMS Physics TDR CPX scenario M.Schumacher et al hep-ph/0608079 Non SUSY models and little Higgs G. Azuelos et al. Eur.Phys.J.direct C4:16,2002 CMS Physics TDR D.Dominici,G.Dewhirst,A.Nikitenko,S.Gennai and L.Fano CMS-NOTE-2005-007 G.Azuelos et al Eur.Phys.J.C39S2:13-24,2005 Invisible Higgs etc ATLAS EP L.Fayard 31-3-2009

  44. Conclusions Many SM Higgs channels have been studied in detail already good sensitivity to SM Higgs with few fb-1 MSSM Higgs sector covered Detailed Higgs studies will require a lot of statistics Be open to more exotic scenarios L.Fayard 31-3-2009

  45. I would like to thank the organizers Abdelhak, Dirk, Michael , Fabienne L.Fayard 31-3-2009

  46. Backup L.Fayard 31-3-2009

  47. Variation with Ecm (1) ggH ( m = 120 GeV) cross section 1.75 times smaller at 10 TeV than at 14 TeV Signal decreases more then Background for   S /  B decreases by about 1.4 for H L.Fayard 31-3-2009

  48. Variation with Ecm (2) L.Fayard 31-3-2009

  49. Variation with Ecm (3) in order to be equivalent to a single TeVatron experiment at 8 fb-1 L.Fayard 31-3-2009

  50. (*) large mtop approximation S.Moch and A.Vogt Phys Lett B631,48,2005 T.Han,G.Valencia and S.Willenbrock Phys Rev Lett 69,3274,1992 Typical uncertainties on cross-section gg 10 % NNnLO (*) VBF 5% NLO WH,ZH 5% NNLO ttH 15% NLO O.Brein,A.Djouadi and R.Harlander Phys.Lett.B579:149-156,2004 W.Beenaker,S.Dittmaier,M.Kramer,B.Plumper, M.Spira and P.Zerwas Phys Rev Lett 87,201805,2001 S.Dawson,C.Jackson,L.Orr,L.Reina and D.Wackeroth Phys.Rev.D68:034022,200 L.Fayard 31-3-2009

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