Neutralino Dark Matter in Light Higgs Boson Scenario

1. Neutralino Dark Matterin Light Higgs Boson Scenario Phys.Lett.B663:330 Masaki Asano (ICRR, University of Tokyo) S. Matsumoto (Toyama Univ.) M. Senami (Kyoto Univ.) H. Sugiyama (SISSA) Collaborator

2. Introduction What is the Light Higgs boson scenario?

3. What is Light Higgs boson Scenario (LHS)? Introduction MSSM withmh < 114.4 GeV is referred to as LHS in this talk. Recent works of LHS: consistency with LEP results, phenomenological aspect and a solution to the little hierarchy problem are discussed. Recently, G.L.Kane, T. T. Wang, B. D. Nelson and L. T. Wang (2005), M. Drees (2005), A. Belyaev, Q. H. Cao, D. Nomura, K. Tobe, C. P. Yuan (2006), S. G. Kim, N. Maekawa, A. Matsuzaki, K. Sakurai, A. I. Sanda, and T. Yoshikawa (2006), S. G. Kim, N. Maekawa, K. I. Nagao, K. Sakurai, and T. Yoshikawa (2008) …….. • Our interest • Is LHS also compatible with GUT and Dark Matter? • We search the region where consistent with • particle physics experiments • cosmological observations. • Possibility of the dark matter direct detection in LHS.

4. Higgs Boson Mass Limit from Direct Search at LEP Introduction ・in SM, Lower limit: mh > 114 GeV (from lack of the direct signal at LEP II) ・in MSSM, There are 2 Higgs doublets. →The coupling can be different! →The LEP limit may be lower than 114 GeV. If sin(β - α) is small, LHS can be realized. tanb = ratio of vevs, a: mixing

5. Higgs Boson Mass Limit from Direct Search at LEP Introduction ・in SM, Lower limit: mh > 114 GeV (from lack of the direct signal at LEP II) ・in MSSM, There are 2 Higgs doublets. →The coupling can be different! →The LEP limit may be lower than 114 GeV. If sin(β - α) is small, LHS can be realized. tanb = ratio of vevs, a: mixing ・in MSSM, we should take care of the other mode. (This mode is suppressed due to the p-wave production as long as mA ~ mZ.)

6. What is Light Higgs boson Scenario (LHS)? Introduction MSSM withmh < 114.4 GeV is referred to as LHS in this talk. Recent works of LHS: consistency with LEP results, phenomenological aspect and a solution to the little hierarchy problem are discussed. Recently, G.L.Kane, T. T. Wang, B. D. Nelson and L. T. Wang (2005), M. Drees (2005), A. Belyaev, Q. H. Cao, D. Nomura, K. Tobe, C. P. Yuan (2006), S. G. Kim, N. Maekawa, A. Matsuzaki, K. Sakurai, A. I. Sanda, and T. Yoshikawa (2006), S. G. Kim, N. Maekawa, K. I. Nagao, K. Sakurai, and T. Yoshikawa (2008) …….. • Our interest • Is LHS also compatible with GUT and Dark Matter? • We search the region where consistent with • particle physics experiments • cosmological observations. • Possibility of the dark matter direct detection in LHS. To avoid ZAh constraint, we investigate around 90 < mh < 114 GeV .

7. LEP has found the excess from expected BG around mh = 98 GeV. Introduction □ 98 GeV ：2.3σexcess □115 GeV ：1.7σexcess 1. SM Higgs can not explain the excess, because the number of the excess events corresponds to about 10% of that predicted in the SM. 2. MSSM maybe explain this excess if the LHS is realized!

8. Light Higgs boson Scenario To realize the LHS, sin(β-α) has to be small.

9. small sin(β- α) Neutral Higgs mass matrix Large radiative corrections Assuming + D Mass eigenstates of neutral Higgs bosons are described by

10. small sin(β- α) , + D usual scenario (mA2 >> mZ2) mA2 Lightest Higgs consists of up-type. → cos α ~ 1 , α ~ 0 → sin(β-α) ~ 1 → gZZh ~ gZZHSM(SM Higgs limit is applied) D mZ2 h (η2)H (η1) LHS (mA2 ~ mZ2) Lightest Higgs consists of down-type. → sin α ~1 , α ~ π/2 → sin(β-α) is small → gZZh << gZZHSM (SM Higgs limit is avoided) D mA2 mZ2 h (η1)H (η2) In LHS, all Higgs bosons are light. mA2 ~ mH±2 ~ mH2 ~ mh2

11. small sin(β- α) , + D usual scenario (mA2 >> mZ2) mA2 Lightest Higgs consists of up-type. → cos α ~ 1 , α ~ 0 → sin(β-α) ~ 1 → gZZh ~ gZZHSM(SM Higgs limit is applied) D mZ2 h (η2)H (η1) LHS (mA2 ~ mZ2) Lightest Higgs consists of down-type. → sin α ~1 , α ~ π/2 → sin(β-α) is small → gZZh << gZZHSM (SM Higgs limit is avoided) D mA2 mZ2 h (η1)H (η2) In LHS, all Higgs bosons are light. mA2 ~ mH±2 ~ mH2 ~ mh2

12. small sin(β- α) , + D usual scenario (mA2 >> mZ2) mA2 Lightest Higgs consists of up-type. → cos α ~ 1 , α ~ 0 → sin(β-α) ~ 1 → gZZh ~ gZZHSM(SM Higgs limit is applied) D mZ2 h (η2)H (η1) LHS (mA2 ~ mZ2) Lightest Higgs consists of down-type. → sin α ~1 , α ~ π/2 → sin(β-α) is small → gZZh << gZZHSM (SM Higgs limit is avoided) D mA2 mZ2 h (η1)H (η2) In LHS, all Higgs bosons are light. mA2 ~ mH±2 ~ mH2 ~ mh2

13. Results (LHS Allowed region in NUHM ) (Non-Universal scalar masses for the Higgs Multiplets) m0, mHu, mHd, m1/2, A0, sign(m) Weak scale m0, m1/2, A0, tanb, m, mA Using this, we can study the MSSM Higgs sector in detail.

14. WMAP allowed region example parameter set funnel co-annihilation Charged LSP

15. WMAP allowed region example parameter set funnel co-annihilation Charged LSP Bs→γ: Light H± contribution should be canceled by chargino one. In particular, light H± contribution can be compensated by large A-terms. A-term

16. example parameter set WMAP allowed region funnel co-annihilation Charged LSP Bs→γ: light H± contribution should be canceled by chargino one. In particular, light H± contribution can be compensated by large A-terms. A-term Bs →μ+μ-: Br(Bs →μμ) ∝ (tanβ)6/(mA)4 Because mA is small, large tanβ ( 20) is excluded. tanβ

17. WMAP allowed region funnel co-annihilation Allowed region Charged LSP Bs→γ: light H± contribution should be canceled by chargino one. In particular, light H± contribution can be compensated by large A-terms. A-term Bs →μ+μ-: Br(Bs →μμ) ∝ (tanβ)6/(mA)4 Because mA is small, large tanβ ( 20) is excluded. tanβ

18. For several value of μ, we search the region which is consistent with following constraints. CONSTRAINTS Parameter Scan tanb = 10 80 < mA < 140 GeV • WMAP • LEP2 Higgs search Zh/ZH & Ah/AH • SUSY particle searches • Color/Charged breaking • Br( b  sγ ) & Br( Bs  μ+μ– ) (m, A0) GeV = (300, –700), (600, –1000), (700, –1100)

19. For several value of μ, we search the region which is consistent with following constraints. CONSTRAINTS Parameter Scan tanb = 10 80 < mA < 140 GeV • WMAP • LEP2 Higgs search Zh/ZH & Ah/AH • SUSY particle searches • Color/Charged breaking • Br( b  sγ ) & Br( Bs  μ+μ– ) (m, A0) GeV = (300, –700), (600, –1000), (700, –1100) • The LHS region consistent with the WMAP observation exists! • Too Large μ is not favored (No region for μ > 800 GeV) funnel region Mixing region coannihilation region

20. Direct detection Because DM often passes through the Earth, DM sometimes interacts with nucleus inside the detector. Direct detection observes nuclear recoil as DM scatter of them.

21. Direct detection … Now, all Higgs are light. Then, prediction for this cross section is large. • Small μ is not favored from direct detection experiments. • 2. Even for large μ, • it is possible to detect the signal at on-going experiments!

22. Direct detection … Now, all Higgs are light. Then, prediction for this cross section is large. • Small μ is not favored from direct detection experiments. • 2. Even for large μ, • it is possible to detect the signal at on-going experiments!

23. Direct detection … Now, all Higgs are light. Then, prediction for this cross section is large. XMASS • Small μ is not favored from direct detection experiments. • 2. Even for large μ, • it is possible to detect the signal at on-going experiments!

24. Summery

25. Summery • Light Higgs Boson Scenario is one of interesting candidates for new physics at TeV scale. • The scenario is consistent with not only particle physics experiments but also cosmological observations. • The scenario predicts a large scattering cross section between dark matter and ordinary matter, thus it will be tested at present direct detection measurements for dark matter. • We will scan all parameter space to search the lower limit of tanβ (which determines lower limit of Br(Bs  μ+μ–) in LHS). Using the limit, LHS can be tested by near future. • Almost all SUSY particles are predicted to be light, these particles will be copiously produced at colliders.