Implications of the 125 GeV Higgs for the inert dark matter

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1 Implications of the 125 GeV Higgs for the inert dark matter Bogumiła Świeżewska Faculty of Physics, University of Warsaw Recontres de Moriond QCD and High Energy Interactions, La Thuile, Italy in collaboration with M. Krawczyk, D. Sokołowska, P. Swaczyna, PRD 88 (2013) , PRD 88 (2013) , JHEP 09 (2013) 055

2 Outline Aim: Constrain the new scalar particles with the use of measured Higgs boson properties. Introduction to IDM LHC Inert DM Implications for the DM combination with PLANCK Detection of the DM

3 Why Inert Doublet Model? Simple extension of the SM (not so many parameters) Rich phenomenology SM-like Higgs boson Viable DM candidate Thermal evolution of the Universe + some conditions for baryogenesis

4 Inert Doublet Model (IDM) [N. G. Deshpande, E. Ma, PRD 18 (1978) 2574, J. F. Gunion, H. E. Haber, G. Kane, S. Dawson, The Higgs Hunter s Guide, 1990 Addison-Wesley, R. Barbieri, L. J. Hall, V. S. Rychkov, PRD 74 (2006) , I. F. Ginzburg, K. A. Kanishev, M. Krawczyk, D. Sokołowska, PRD 82 (2010) ] IDM a 2HDM with the scalar potential (real parameters): [ ] ] V = 1 2 m11 2 (φ S φ S) + m22 2 (φ D φ D) [λ 1 (φ S φ S) 2 + λ 2 (φ D φ D) 2 ] +λ 3 (φ S φ S)(φ D φ D) + λ 4 (φ S φ D)(φ D φ S) λ 5 [(φ S φ D) 2 + (φ D φ S) 2 Z 2 symmetry: φ D φ D, φ S φ S (called D) Yukawa interactions: type I (only φ S couples to fermions) L D-symmetric D-symmetric vacuum state φ S = v 2, φ D = 0 EXACT D-symmetry

5 Particle spectrum of IDM [E. M. Dolle, S. Su, Phys. Rev. D 80 (2009) , L. Lopez Honorez, E. Nezri, F. J. Oliver, M. Tytgat, JCAP 0702 (2007) 028, D. Sokołowska, arxiv: [hep-ph]] φ S : h SM-like Higgs boson, tree-level couplings to fermions and gauge bosons like in the SM. Deviation from SM in loop couplings possible! φ D : H, A, H ± D-odd dark scalars, no tree-level couplings to fermions D symmetry exact lightest D-odd particle stable DM candidate DM= H, so M H < M H ±, M A

6 Invisible decays of the Higgs boson h HH invisible decay (H is stable) h H H augmented total width of the Higgs boson, Γ(h HH) λ LHC: Br(h inv) < 37% global fit: Br(h inv) 20% bounds on the mass of DM and λ 345 see the talk of P. Meridiani For M H = 50 GeV, M A = 58 GeV. [G. Bélanger, B. Dumont, U. Ellwanger, J. F. Gunion, S. Kraml, PLB 723 (2013) 340]

7 Two-photon decay of the Higgs boson, h γγ At the loop level in the SM γ h h W f γ γ γ In the IDM additional H ± h H ± γ γ Width of h γγ modified for invisible channels closed Γ(h γγ) IDM = G F α 2 Mh π 3 ASM + 2M2 H ± + ( m2 22 4M 2 ) 2M 2 A H ± 2 0 H ± M 2 h

8 Signal strength in the h γγ channel R γγ signal strength R γγ = σ(pp h γγ)idm σ(pp h γγ) SM Γ(h γγ)idm Γ(h) SM Γ(h γγ) SM Γ(h) IDM R γγ can differ from the SM value R γγ = 1 because of: invisible decays (in Γ(h) IDM ) the effect of the DM H ± loop (in Γ(h γγ) IDM ) the effect of the charged scalar For now: R γγ = (ATLAS), R γγ = 0.78 ± 0.27 (CMS) [ATLAS Collaboration, PLB 726 (2013) 88, CMS Collaboration, CMS PAS HIG (2013)]

9 [A. Arhrib, R. Benbrik, N. Gaur, PRD 85 (2012) , BŚ, M. Krawczyk, PRD 88 (2013) ] R γγ > 1 and the masses of the dark scalars Mass of the charged scalar Mass of the DM If R γγ > 1.2: M H, M H ± 154 GeV. Fairly light charged scalar If R γγ > 1: M H > M h /2 Light ( 63 GeV) DM excluded

10 Inert DM relic density constraints Higgs portal DM coupling to fermions through h hhh coupling λ 345 important for the relic density H h f H W H h W H f H W H W < Ω DM h 2 < (3σ, WMAP) < Ω DM h 2 < (3σ, PLANCK) Possible masses: light DM: M H 10 GeV, λ 345 O(0.5) intermediate DM: 40 GeV M H 160 GeV, λ 345 O(0.05) heavy DM: M H 500 GeV, λ 345 O(0.1) [E. M. Dolle, S. Su, Phys. Rev. D 80 (2009) , L. Lopez Honorez, E. Nezri, F. J. Oliver, M. Tytgat, JCAP 0702 (2007) 028, D. Sokołowska, arxiv: [hep-ph]]

11 Constraints from R γγ [M. Krawczyk, D. Sokołowska, P. Swaczyna, BŚ, JHEP 09 (2013) 055] 1.0 Setting a lower limit on R γγ constrains λ 345 Upper and lower limits on λ 345 depend on M H RΓΓ Λ 345,min Λ 345,max R ΓΓ 0.7 R ΓΓ Λ 345 Λ 345 For M H = 55 GeV, M A = 60 GeV, M H ± = 120 GeV Does it agree with the PLANCK measurements?

12 Light DM M H 10 GeV 0.04 M A M h 2 correct relic density λ 345 O(0.5) too small λ 345 overclosing the Universe R γγ > 0.7 λ 345 < 0.04 Λ M H ± GeV M H GeV Light DM exlucded [D. Sokołowska, arxiv: [hep-ph]; Scalars 2013]

13 Intermediate DM [Planck update: D. Sokołowska, P. Swaczyna, 2014] h HH open h HH closed 0.10 M A M H ± 120 GeV R ΓΓ 0.2 A H ± 50 GeV R ΓΓ Λ Planck excluded 0.5 Λ red - agreement with Planck Planck excluded M H GeV 50 GeV < M H < M h /2, M A = M H ± = 120 GeV R γγ > 0.7 & PLANCK M H > 53 GeV M H GeV M h /2 < M H < 83 GeV, M A = M H ± = M H + 50 GeV agreement with PLANCK and R γγ > 0.7, but then R γγ < 1

14 Heavy DM M H > 500 GeV, M A = M H ± = M H + 1 GeV (because of S, T ) 0.4 A H ± 1 GeV R ΓΓ Λ Planck excluded M H GeV Agreement with PLANCK and R γγ 1.

15 Direct detection comparison with XENON/LUX DM-nucleon scattering cross section σ DM N λ R γγ bounds on λ 345 translated to the (σ DM N, M H ) plane XENON10 M H ± GeV ΣDM,N pb XENON M H GeV from the talk of P. Meridiani Constraints from R γγ > 0.7, 0.8 are stronger/comparable to LHC and LUX results.

16 Direct detection comparison with XENON/LUX DM-nucleon scattering cross section σ DM N λ R γγ bounds on λ 345 translated to the (σ DM N, M H ) plane XENON10 M H ± GeV ΣDM,N pb XENON M H GeV from the talk of P. Meridiani Constraints from R γγ > 0.7, 0.8 are stronger/comparable to LHC and LUX results.

17 Summary IDM in agreement with the data (LEP, LHC and PLANCK) h γγ can provide important information about IDM, because it is sensitive to M H and M H ± If R γγ combined with PLANCK constraints on DM scenarios

18 Back up

19 h γγ vs h Zγ [BŚ, M. Krawczyk, Phys. Rev. D 88 (2013) , formulas for h Zγ: A. Djouadi, Phys.Rept. 459 (2008) 1, C.-S. Chen, C.-Q. Geng, D. Huang, L.-H. Tsai, Phys.Rev.D 87 (2013) ] Sensitivity to invisible channels R γγ and R Zγ positively correlated R γγ > 1 R Zγ > 1

20 Constraints on the Higgs decay width Γ Γ SM < 4.2 constraints on h HH 0.15 see the talk of N. De Fillipis Λ M H The bounds are weaker than from constraints on Br(h inv).

21 Direct detection dependence on f N. DM-nucleon scattering cross section σ DM,N λ σ DM,N = λ2 345 mn 4 4πMh 4 (m N + M H ) 2 f N 2 Depends on the value of f N, no agreement on its precise value. f N (0.014, 0.66). We use f N = the middle value.

22 Constraints Vacuum stability: scalar potential V bounded from below Perturbative unitarity: eigenvalues Λ i of the high-energy scattering matrix fulfill the condition Λ i < 8π Existence of the Inert vacuum: Inert state a global minimum of the scalar potential m GeV 2 H as DM candidate: M H < M A, M H ± and WMAP Electroweak Precision Tests (EWPT): S and T within 2σ (S = 0.03 ± 0.09, T = 0.07 ± 0.08, with correlation of 87%) LEP bounds on the scalars masses LHC: M h 125 GeV

23 Masses of the scalars Mh 2 = m2 11 = λ 1v 2 MH 2 ± = 1 2 (λ 3v 2 m22 2 ) MA 2 = 1 2 (λ 345 v 2 m22 2 ) MH 2 = 1 2 (λ 345v 2 m22 2 )

24 R γγ > 1 analytical solution If invisible channels closed R γγ = Γ(h γγ)idm Γ(h γγ) SM R γγ > 1 can be solved analytically for M H ±, m 2 22 Constructive interference m 2 22 < 2M2 H ± ( λ 3 < 0) with LEP bound on M H ± m 2 22 < GeV 2 Destructive interference IDM contribution 2 SM contribution big m 2 22 required: m GeV 2 excluded by the condition for the Inert vacuum m GeV 2

25 DM signals [see e.g.: M. Gustafsson, S. Rydbeck, L. Lopez Honorez, E. Löndstrom, Phys. Rev. D 86 (2012) ] gamma-ray lines cosmic and neutrino fluxes direct detection signals