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M. Asano (Tohoku Univ.) M. Senami (Kyoto Univ.) H. Sugiyama (Ritsumeikan Univ.) PowerPoint Presentation
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M. Asano (Tohoku Univ.) M. Senami (Kyoto Univ.) H. Sugiyama (Ritsumeikan Univ.)

M. Asano (Tohoku Univ.) M. Senami (Kyoto Univ.) H. Sugiyama (Ritsumeikan Univ.)

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M. Asano (Tohoku Univ.) M. Senami (Kyoto Univ.) H. Sugiyama (Ritsumeikan Univ.)

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  1. Comprehensive Analysis on the Light Higgs Scenario in the Framework of Non-Universal Higgs Mass Model Shigeki Matsumoto Collaborators M. Asano (Tohoku Univ.) M. Senami (Kyoto Univ.) H. Sugiyama (Ritsumeikan Univ.)

  2. New Physics @ Tera-scale The Standard Model (SM) is one of the most successful models describing physics below O(100) GeV. There are, however, some problems that can not be explained in this framework. ~ Hierarchy Problem ~ Tree level mass (m02) Quantum Corrections mh2 = + O(102 GeV)2 O(10-2)L2 The cutoff scale L should be smaller than O(1) TeV. ~ Dark Matter Problem ~ No candidate for dark matter in the SM. WIMP seems to be natural for the DM. Neutral & Stable particle with O(1) TeV mass  Cold DM & Correct Relic Density of DM! New particle (dark matter) will be at O(1) TeV.

  3. New Physics @ Tera-scale The Standard Model should be regarded as an effective field theory describing physics below 100 GeV. New Physics appears at O(1) TeV, and it will solve the problems. E (GeV) New Physics scenarios! Supersymmetric Scenario Little Higgs Scenario Extra-dimension Scenario Gauge Higgs Scenario, etc. SUSY scenario gives the solution to the both problems! New Physics @ 1 TeV Scale 103 (10-16cm) 102 Which SUSY model we consider? MSSM Gauge sym: SU(3)×SU(2)×U(1) Part. cont: Li, Ei, Qi, Di, Ui, H1, H2 Standard Model (10-15cm)

  4. The Light Higgs Scenario (LHS) We focus on the parameter region of the LHS! Explaining the LEP anomaly [M. Drees, PRD71 (2005)] Collider signals at the LHC [A. Belyaev, et.al., PRL100, (2008)] Relaxing the little hierarchy Problem [S. G. Kim, et.al., PRD74, (2006)] In the MSSM, there are two Higgs doublets:H1 & H2 For down-type quarks For up-type quarks CP-odd Scalars Charged Scalars

  5. The Light Higgs Scenario (LHS) We focus on the parameter region of the LHS! Explaining the LEP anomaly [M. Drees, PRD71 (2005)] Collider signals at the LHC [A. Belyaev, et.al., PRL100, (2008)] Relaxing the little hierarchy Problem [S. G. Kim, et.al., PRD74, (2006)] In the MSSM, there are two Higgs doublets:H1 & H2 For down-type quarks For up-type quarks CP-even Scalars K

  6. The Light Higgs Scenario (LHS) e When Radiativecorrection + D e Usual case LHS case sin & & mA D mZ D mZ h ~ η1 H ~ η2 h ~ η2 H ~ η1 All Higgs bosons are light! SM-like Higgs boson!

  7. Constraints on the Higgs sector of LHS ~ Bound on mh~ Usual case (mA >> mZ) h ~ η2 gZZh (gZZh)MSSM~ (gZZh)SM LEP bound on mh > 114.4 GeV LHS case (mA~mZ) h ~ η1 (gZZh)MSSM <<(gZZh)SM No LEP bound! Possible to explain the LEP Anomaly

  8. Constraints on the Higgs sector of LHS , H The LEP limit is avoided for the Lightest Higgs boson (h) The LEP limit is applied to the Heavy Higgs boson (H). This mode is suppressed due to the P-wave production as long as mA~mZ (mA is not too small.)

  9. Realization of the Light Higgs Boson Scenario Purpose: Dark Matter phenomenology in the LHS Purpose: Dark Matter phenomenology in the LHS MSSM has many parameters, so that it is difficult to handle with the model to explore the region realizing the LHS. We have considered the NUHM (Non-universal Higgs Mass) model, which can realize the LHS. In this model, GUT relation on gaugino masses is assumed. E (GeV) m0, mH1, mH2, m1/2, A0, B, m GUT Parameters m0, m1/2, A0,tanb, m, mA Through RGEs Masses of SUSY particles, Higgs masses, v, tanb, … 1 TeV

  10. Realization of the Light Higgs Boson Scenario Constraints on NUHM With the use of MCMC method, we have generated about 3.0 x 107 sample points which satisfy above constraints.

  11. Realization of the Light Higgs Boson Scenario Contour of Maximal Likelihood P = exp(-c2/2) The LHS Region The NUHM model realize the LHS region of the MSSM!

  12. Realization of the Light Higgs Boson Scenario Allowed Region on the input parameter space 100 GeV < m1/2 < 600 GeV 100 GeV < m0 < 1.9 TeV 7 < tan b < 19 93 GeV < mA < 113 GeV 200 GeV < m < 850 GeV -3.5 TeV < A0 < 100 GeV

  13. DM in the LHS • M. Asano, S. M., M. Senami, and H. Sugiyama, PLB663 (2008) • S.-G. Kim, N. Maekawa, K. I. Nagao, K. Sakurai, T. Yoshikawa, PRD78 (2008) • M. Asano, S.M., M. Senami, and H. Sugiyama, JHEP 1007 (2010) • What is the Dark Matter? (Ans.) The Lightest neutralino! • Composition of the DM? (Ans.) Almost Bino-like! • Mass of the DM? (Ans.) 50 GeV < mDM < 300 GeV Contamination of higgsino components in the DM (Bound on Chargino mass) I. Chargino mass > LEP search II. Chargino mass < Br(bsγ) 100 GeV < m1/2 < 600 GeV

  14. DM in the LHS 90% C.L. on SI cross section arXiv:1005.0380 CDMSII XENON100 XMASS SuperCDMS

  15. DM in the LHS Lower Bound! sDM N >7 x 10-45 cm2 All higgs bosons are light.

  16. DM in the LHS ~ SUSY Little Hierarchy Problem ~ How severe fine-tuning is needed for the EW scale? A few % fine-tuning is needed. (In CMSSM, typically 0.1%)

  17. Implication to the LHC LHS spectrum Mass (GeV) Spectrum is very similar to that of SPS1a’ except the Higgs sector. 1. Confirmation of the LHS by measuring a~ p/2. 2. Confirmation of the WIMP by measuring WDMh2.

  18. Summary & Discussions • The Standard Model is the successful model to describe physics below the scale of O(100) GeV. However, there are some problems which can not been explained in this framework, and the existence of "New Physics” is expected to solve these problems naturally. • Many scenarios of the New Physics have been proposed so far, and supersymmetric scenario is one of the most attractive scenarios. In this talk, we have focused on the Light Higgs Boson Scenario (LHS) of the MSSM. It is shown that the NUHM model realizes the LHS. • One of interesting predictions of the LHS is coming from dark matter phenomenology. In this model, the mass of the dark matter is expected to be about 100 GeV, and its scattering cross section with a nucleon is about 10-44cm2. As a result, the dark matter in the LHS can be easily discovered in near future direct detection experiments. • Since almost all new particles are predicted to be light, it is interesting to consider signals of new physics at the LHC. It is also interesting to consider signals at the ILC, because higgs sector of the scenario can be explored carefully.

  19. Current Status of Higgs Boson ~ MSSM Higgs ~ Status of MSSM Higgs MSSM Higgs Interactions LEP collaboration have also analyzed constraints on MSSM Higgs bosons MSSM contains 2 Higgs doublets  Higgs interactions can be different! However, analysis have been performed in some MSSM benchmark scenarios, but not in all MSSM parameter space! (The parameter space is too large!!) ~ some details of benchmarks ~ 1. m and At term are fixed in some specific values 2. mA & tanb are scanned within specific ranges tanb = ratio of vevs, a: mixing The LEP limit may not be applied to the MSSM Higgs bosons

  20. Current Status of Higgs Boson MSSM Benchmarks For example, No Mixing case. We can find the LHS region. However, the LHS region is only a part of the benchmark, The choice of the parameter space is not useful.