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Non SM Higgs Prospects @ LHC

This study delves into the prospects for discovering MSSM Higgs bosons at the LHC, with a focus on the CP-violating Higgs sector. The analysis considers various scenarios, including the Gluophobic Benchmark, and discusses coupling preferences, decay widths, and production processes. Key channels such as VBF and WW, tt, and gg decays are examined, highlighting the complementarity between different Higgs bosons. The study defines criteria for discovery and addresses challenges in identifying MSSM Higgs bosons amidst the Standard Model background.

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Non SM Higgs Prospects @ LHC

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  1. Non SM Higgs Prospects @ LHC Acknowledgements:Markus Schumacher • MSSM CPC Higgs Sector • Prospects for MSSM Higgs Discovery • MSSM CPV Higgs Sector • Prospects for MSSM CPV Higgs Discovery Eilam Gross Weizmann institute of Science/ATLAS Sabine Kraml The flowering of the Higgs physics that is expected to bloom at the TeV scalefrom the CPNSH report: the hitchhikers guide to non-standard Higgs physics To be published as a CERN yellow report http://kraml.home.cern.ch/kraml/cpnsh/ Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  2. MSSM • In the MSSM model there are 5 Higgs bosons: h,H,A and H+,H- • The relation between the SM and light SUSY Higgs couplings is given bywhere ais the mixing angle between the two scalar Higgs bosons and tgbis the ratio between the two vacuum expectation values Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  3. q H q The h/H Production Processes @ LHC MAXMH Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  4. diagonalization Radiative Corrections • Allow mixing ( )between scalar stop quarks (with large tgb) can push the light Higgs mass upper with a maximum of ~135 GeV • Different mixings various scenarios (benchmarks) • MHMAX • No Mixing • Gluophobic: Suppressed hgg coupling • Small aeffSuppressed hbb,htt coupling Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  5. The Gluophobic Benchmark • The GGF process is not necessarily the dominant one. SUSY loops might reduce it. In the GLUOPHOBIC scenario thetop-stop loopssuppress the GGF cross section. Gluophobic Min Mix Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  6. Couplings & Decay Widths • The Higgs couple to MASS  prefers downtype leptons (t) and b-quark • Note how hgg is suppressed for high tgb and Agg is forbidden Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  7. Couplings & Decay Widths • For large values of tgb ; tgb>>1tgb~1/cosb; cosb<<1 and small values of mAmA~mh, cos2(a-b)~sin2a~1Large Gh • Large tgbLarge GA • Large decay widths reduce the signal sensitivity with respect to the SM channels. A correction factor is applied h Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  8. Couplings & Decay Widths • For large values of tgb ; tgb>>1tgb~1/cosb; cosb<<1 and small values of mAmA~mh, cos2(a-b)~sin2a~1Large Gh • Large tgbLarge GA, Large mALarge GH K = Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  9. Analysis is mostly based on ATLAS fast simulation. Trigger efficiencey, Mass resolutions & Particle ID all based on Full Simulation Luminosity considered is Low luminosity 30 fb-1(1st three years LHC) High luminosity (+ pile up..) +270 fb-1(another ~3-4 years) q H q g t H t g t g H g q W W H q g t t b H+ Towards Experiment Channels taken into consideration Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  10. When a SM analysis was applied correction factors were uses….e.g. LO cross sections were used (conservative!) A correction for widths was applied An increase of sensitivity was taken into account when two independent channels (e.g. H,h) overlapped. Dedicate searches bbh/H/A with Higgsmm,ttand for Charged Higgs Towards Experiment Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  11. Definition of Discovery • Each channel was consideredwith its corresponding background, and an excess was considered adiscovery if the probability of the background fluctuating to the expected background+signal is less than 2.85x10-7 (poissonian, equivalent to 5 sigmas) Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  12. The Challenge • Can we discover MSSM ? • Which Higgs can we observe? H? h? A? H+? • If we observe a scalar, can we tell if it’s a SM Higgs? h? A? H+? H? Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  13. VBF is related to the MSSM Higgs coupling ghVV~sin2(a-b), gHVV~cos2(a-b)  Complementarity Note that the H coupling is suppressed at large mA The VBF is important for h close to its maximal mass (large mA) and H at its lower mass bound q H q VBF H and h Production Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  14. VBF H,hWW No mass reconstructionNeed to understandWW BG Higgs mass & ghVV too smallBoth Production & Decay suppressed s(qqqqh)xBR(hWW*) low ATLAS preliminary 30 fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  15. VBF H,htt ETmiss resolutiont tag(including t jet) ATLAS preliminary 30 fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  16. H,h,Agg Good mass resolution & photon identification compensates for the poor BR ATLAS preliminary 300 fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  17. GGF H,hZZ4l • A gold plated channel for SM Higgs (due to the excellent e/m identification) • The heavier the light h the bigger the BR(hZZ*) , • H & h are complementary, the heavier the A, the HZZ coupling suppressedA does not couple to ZZ • In the no mixing scenario the Higgs is lighter and the BR(hZZ*) is a killer Higgs mass & ghVV too small BR(hZZ*) too low ATLAS Preliminary 300fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  18. ATLAS Preliminary 300fb-1 ttH tth ttH,tthttbb • ttH/h is complementary to the H/hZZ Low mAlow mhIncreasing xsc Low tgbghtt increasesIncreasing xsc Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  19. ttH,tthttbb • ttH/h is complementary to the H/hZZ • In the minimal mixing the h mass is smaller and the coverage is full ATLAS Preliminary 300fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  20. Channels studies with Higgsmm,tt Channels contribute for large tgb since all couplings are enhanced wrt SM couplings by ~1/cosb and H and h are complementary The Muonic decay mode suffers from very low BR but a clean signature ppbbh, bbH, bbA Increasinggs 30fb-1 300fb-1 Decreasings ATLASPRELIMINARY Kink @ 450 Gev due to Htthad had Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  21. Charged Higgs • tree level mH+2 = mA2 + mW2 • Rad Corrs:Charged Higgs mass can be pushed down below the W mass • For mA<150, mH+<mtoptH+b opens mtop Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  22. Charged Higgs Boson • Dominant decay mode to tn until the phase space for the top quark opens(at ~160 GeV) • For mH+<mtop (mA<150)the dominant decay mode is to tn while for mH+>mtop (mA>150)the dominant decay mode is to tb for low tgb Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  23. Production of Charged Higgs @ LHC • Dominant production modes: For mA>150 • Signal gbtH+ttb,ttnggtbH+ • Dominant production modes for mA<150 via the decay of a top quark pptt, t H+ b Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  24. Discovery Sensitivity for Charged Higgs • tn decay is decreasingasmAis increasing but scales up with increasing tgb (coupling ~mt tgb) 30 fb-1 300 fb-1 Increasinggtn tt BG ATLASPRELIMINARY Decreasingtn Mtop Transition region requires study ATLAS preliminary Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  25. Discovery Sensitivity for h • For minimal mixing it seems the coverage is full Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  26. Discovery Sensitivity for h • VBF (hVV) decouples for high tgb and low mAMust use bbh, however… • The htt has DY background and no mass reconstruction possible. hmm is cleaner but with a very small BR.It also decreases with decreasing tgb • Therefore for small mA the bbh with hmm leaves a holetowards lower tgb • There the complementary VBF Htt will cover Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  27. Overall Sensitivity • In a large region only one light Higgs is observed Lone Higgs • SM or SUSY Higgs? • The challenge of the LHC or the place where LHC/ILC meet Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  28. Excluded by LEP Overall Sensitivity • There is a full coverage in all benchmarks! • Can the Lone Higgs region be probed for NonSM evidence? Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  29. A/H->c20c20->4l + ETmiss • Sensitivity in very specific points in the MSUGRA SUSY phase space CMS Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  30. A Way Around the Hole JHEP 0409 : 062 , 2004, Desch, E.G., Heinemeyer, Weiglein, Zivkoviic Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  31. A Way Around the Hole hep-ph/0407190Weiglein et. al. It will take a lot of luminosity from LHC to get reasonable BRs accuracies Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  32. CPV MSSM Higgs • Can h,H and A mix? • With complex trilinear couplings At,b • No more well defined mA , the only remaining well defined mass parameter is mH+ • mH1<mH2<mH3 • The CPX scenario is defined with Arg(At,b)=90o providing maximal mixing in the Higgs sector Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  33. Decay Modes of CPV Higgs • In the CPC case,are forbidden A  hh ,WW ,ZZ and HhZ Production VBF ; ppttHi, bbHi ; ppHi & ttH+bWb, gbH+t Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  34. Decay Modes of CPV Higgs • In the CPC case there is no coupling gAVVNote that for mH+<150 the H1 decouples from the V Bosons Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  35. LEP results • Loss of sensitivity around tgb~3-10 due to complexity of final states(ZH26 jets… H1H2bbbb etc.)and insensitivity to very low Higgs mass Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  36. ATLAS Sensitivity to H1 30fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  37. ATLAS Sensitivity to H1 • The hole is due to: • H1VV (decay and VBF) suppression for lighter H+ and decreasing tgb • ttH production mode is strongly suppressed for high tgb 30fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  38. ATLAS Sensitivity to H2,3 30fb-1 • The bbH cross section is decreasing with increasing H massand decreasing tgb • There is a reduction in the tt decay BR in favour of bb and H2H1H1 while light H1 was not yet studied for LHC Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  39. ATLAS Sensitivity to H+ 30fb-1 • Similar to CPC case (H+ is the only surviving Higgs mass eigenstate) Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  40. Overall Sensitivity • Looks complete…HOWEVER 300 fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  41. Overall Sensitivity • The hole corresponds to light Higgs mH1<70, mH+<mtop • For each i • Hole might be covered with additional analysis of tt with one top tbH+bWH1 and another top decaying leptonically 300 fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  42. CPV Overall Sensitivity 300 fb-1 Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  43. CPC Conclusions Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  44. CPC Conclusions • For the CP conserving MSSM Higgs, all of the parameters space is potentially covered (30 fb-1) by the prospective discovery of at least one Higgs boson • This coverage is seen in all benchmark scenarios and therefore reflects probably most of the MSSM phasespace • In a Large region of the parameters space only the light SM like Higgs Boson might be observed (the “lone Higgs region”) and LHC challenge would be to tell if it is a SM Higgs Boson • More thought and creative ideas are needed to fill the “lone Higgs region” with more observed Higgs Bosons Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

  45. CPV Conclusions • For the CP violating MSSM Higgs, although most of the parameters space is potentially covered by observing at least one Higgs Boson(300 fb-1) there is still a hole and further study is needed. • An LHC dedicated low mass Higgs (below 70 GeV) analysis is necessary for the CPV case. An extended study of low mass Charged Higgs could improve the potential coverage Eilam Gross, Weizmann Institute, NSMHiggs , ichep06, Moscow

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