Neutralino Dark Matter in Light Higgs Boson Scenario (LHS) The scenario is consistent with  particle physics experiments Particle mass b → sγ Bs →μ + μ -  cosmological observations WMAP. Allowed region can be judged by Bs →μμ& direct detection. Masaki Asano (SOKENDAI) Collaborator S. Matsumoto M. Senami H. Sugiyama arXiv: We show

Current Status of Higgs Boson SM tan  = ratio of vevs,  : mixing Direct LEP Search at LEP To avoid the strong constraint from ZAh process, we investigate around 90 < m h < 114 GeV in LHS. MSSM MSSM contains 2 Higgs doublets  The coupling can be different! The LEP lower limit may be lower than 114 GeV. If sin(β-α) is suppressed, we have to take care of the mode This mode is suppressed due to the P-wave production as long as m A ~ m Z (m A is not too small.)

Introduction Hierarchy Problem is solved Dark Matter existence GUT is improved as compared to SM 1. Supersymmetry 2. Higgs Potential in MSSM V=V= gauge coupling ! MSSM predicts light Higgs boson m h ~ m Z 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! 3. LEP has found the excess from expected BG around 98 GeV Why LHS (90 < m h < 114GeV) in MSSM?

Introduction to LHS Assuming  Case  Usual Scenario LHS Scenario To realize the LHS, Sin(β-α) has to be small. sin SM Higgs limit is applied SM Higgs limit is avoided

CMSSM (Constrained MSSM) m 0, m 1/2, A 0, tan , sign  Usually people use CMSSM as reference model for the MSSM, which is used for collider physics, dark matter phenomenology, etc. NUHM (Non-Universal Higgs Mass model) Unfortunately, LHS is not realized. m 0, m Hu, m Hd, m 1/2, A 0, sign(  m 0, m 1/2, A 0, tan , , m A Weak scale Higgs mass parameters (m Hu & m Hd ) are not necessarily unified with m 0. Higgs sector has more freedom! LHS is realized in the NUHM 1.squark, slepton mass universality are necessary due to suppress unwanted FCNC. 2. Universal gaugeino mass is motivated by GUT. 3. Universal trilinear coupling is also necessary due to suppress unwanted FCNC. 1, 2, 3

Region consistent with WMAP and other constraints in the LHS CONSTRAINTS Parameter Scan 80 < m A < 140 GeV tan  = 10 ( , A 0 ) GeV = (300, –700), (600, –1000), (700, –1100) WMAP LEP2 Higgs search Zh/ZH & Ah/AH SUSY particle searches Color/Charged breaking Br( b  sγ ) & Br( B s  μ + μ – ) (because of m A ~ m H + ~ m h, tanβ >>1 ) Pseudo-funnel region Mixing region Pseudo-coannihilation region Too Large μ is not favored (No region for μ > 800 GeV) The LHS region consistent with the WMAP observation exists!

Can we expect signatures at Dark Matter experiments?  Yes, at direct detection experiments for dark matter! Can we expect signatures at Dark Matter experiments?  Yes, at direct detection experiments for dark matter! Crystal (Ge, Xe, …) Observing the release energy 1.Dark matter forms the halo associated with Galaxies. 2.Solar system moves inside the halo 3.Dark matter often passes through the Earth. 4.Dark matter sometimes interacts with nucleus inside the detector. Direct detection observes nuclear recoil as DM scatter of them.

Direct detection … Now, all Higgs are light. Then, prediction for this cross section is large. 1.Small mu is not favored from direct detection experiments. 2. Even for large mu, it is possible to detect the signal at on-going experiments!

Summary 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. Discussion It is interesting to consider the connection between cosmology and collider physics at LHC & ILC. Almost all SUSY particles are predicted to be light, these particles will be copiously produced at colliders. Then, it is possible to establish the connection by comparing the result at colliders and CMB experiments and direct detection measurements for dark matter.