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Fingerprinting of the Higgs boson couplings as a probe of new physics models

Fingerprinting of the Higgs boson couplings as a probe of new physics models. Kei Yagyu (National Central U.). The 11 th LHC Physics Monthly Meeting, KIAS, Feb. 18, 2014. Congratulation!. 이 상화. Figure Skating (20 th and 21 st ). 김 연아. 浅田 真央. Minimal (1 doublet). Explained.

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Fingerprinting of the Higgs boson couplings as a probe of new physics models

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  1. Fingerprinting of the Higgs boson couplings as a probe of new physics models Kei Yagyu (National Central U.) The 11th LHC Physics Monthly Meeting, KIAS, Feb. 18, 2014

  2. Congratulation! 이 상화

  3. Figure Skating(20th and 21st) 김연아 浅田 真央

  4. Minimal (1 doublet) Explained EW data, Flavor, … 126 GeV Higgs

  5. Extended Higgs sectors Singlets Doublets Triplets… Minimal (1 doublet) Extra Explained EW data, Flavor, … 126 GeV Higgs

  6. Neutrino mass, Dark matter and Baryon asymmetry Introduce Extended Higgs sectors Singlets Doublets Triplets… Minimal (1 doublet) Extra Explained EW data, Flavor, … Beyond the SM 126 GeV Higgs

  7. Neutrino mass, Dark matter and Baryon asymmetry Determine Extended Higgs sectors Singlets Doublets Triplets… Minimal (1 doublet) Extra Determine EW data, Flavor, … Beyond the SM 126 GeV Higgs Higgs prop.

  8. Neutrino mass, Dark matter and Baryon asymmetry Determine Extended Higgs sectors Singlets Doublets Triplets… Bottom up Approach! Minimal (1 doublet) Extra Determine EW data, Flavor, … Beyond the SM 126 GeV Higgs Higgs prop.

  9. Bottom up Approach 2. Indirect search 1. Direct search Measuring effects on the 126 GeV Higgs boson Energy Discovery Energy H++, H+, H, A, ... h h 126 GeV H++, H+, H, A, … 126 GeV Studying both ways is important to determine the structure of the Higgs sector.

  10. Bottom up Approach 2. Indirect search 1. Direct search Measuring effects on the 126 GeV Higgs boson Energy Discovery Energy H++, H+, H, A, ... h h 126 GeV H++, H+, H, A, … 126 GeV Studying both ways is important to determine the structure of the Higgs sector.

  11. Indirect Search Indirect search = Precision test of Higgs couplings Experiments Theory hVV Minimal Singlet Models 2HDMs Triplet Models etc… hbb hττ Compare hcc hγγ hhh Make a “Fingerprint” from precise measurements. • Patterns of deviation in various Higgs couplings strongly depend on the structure of the Higgs sector.

  12. Higgs coupling measurements ILC, TDR ILC, Higgs White Paper, arXiv: 1310.0763 (300/fb) The hZZ coupling can be measured by 1 % accuracy at the ILC(250) !

  13. Higgs coupling measurements ILC, TDR ILC, Higgs White Paper, arXiv: 1310.0763 (300/fb) The hVV and hffcouplings can be measured by 1 % accuracy at the ILC(500) !!

  14. Higgs coupling measurements ILC, TDR ILC, Higgs White Paper, arXiv: 1310.0763 (300/fb) The hVV and hffcouplings can be measured by 1 % accuracy at the ILC(500) !!

  15. Contents • Introduction • - Bottom up approach (Indirect search) • Deviations in the Higgs boson couplings in various Higgs sectors • - The hVV and hff couplings at the tree level • Higgs boson couplings in the 2HDMs • - Tree level • - One-loop level • Summery

  16. Basic Constraints There are two guidelines to restrict Higgs sectors. 1. Electroweak rho parameter +0.0003 ρexp =1.0004 -0.0004 Models with ρtree = 1 seems to be a natural choice. Satisfy the relation Alignment of (exotic) VEVs Ex. Model with doublet (Y=1/2) + triplet (Y=1) + triplet (Y=0) (Georgi-Machacek model) if

  17. Basic Constraints There are two guidelines to restrict Higgs sectors. 2. Flavor Changing Neutral Current(FCNC) Tree level FCNC process should be absent. In general, multi-doublet extensions cause FCNC at the tree level B0 B0 Φ0

  18. Basic Constraints There are two guidelines to restrict Higgs sectors. 2. Flavor Changing Neutral Current(FCNC) Tree level FCNC process should be absent. In general, multi-doublet extensions cause FCNC at the tree level B0 B0 Only one Higgs doublet couples to each fermion. Φ0

  19. Simple Extended Higgs Sectors We consider the following simple Higgs sectors; (with ρtree = 1 and no tree level FCNC) 1. Φ + S (Singlet) 2. Φ + D (Doublet) 3. Φ + Δ (Triplets or larger) [GM model, Septet model] Hisano, Tsumura, PRD87 (2013) Kanemura, Kikuchi, KY, PRD88 (2013)

  20. Two mixing angles • Mixing between CP-even states • VEVs T: isospin, Y:hypercharge where

  21. Deviations in hff and hVV • Yukawa f α φ Φ β V <φ> Yf = mf /<Φ> f <Φ> V φ Φ V V • Gauge β <φ> α

  22. Higgs Singlet Model (φ=S) • Yukawa f ★ The singlet VEV does not contribute to the EWSB. → β=0 (<Φ>=246 GeV) α S Φ V <S> Yf = mf /<Φ> f <Φ> V S ★ The hff and hVV couplings are universally suppressed. Φ V V • Gauge <S> α

  23. Two Higgs Doublet Model (φ=D) • Yukawa f ★There are 2 patterns in κf for each fermion f. α β D (Φ) Φ (D) <D (Φ)> Yf = mf /<Φ (D)> f V ★ξ = 1 <Φ> V D Φ V V • Gauge β <D> α

  24. Model with a triplet (or higher) (φ=Δ) • Yukawa ★The hff couplings are universally suppressed. f α β Δ Φ ★ξ factor can be larger than unity. → κV > 1 V <Δ> Yf = mf /<Φ> f <Φ> V Δ Ex. GM model: ξ = 2*sqrt(6)/3 Septet model : ξ = 4 Φ V V • Gauge β <Δ> α

  25. SM

  26. κF’ SM

  27. κF’ κF = κF’ SM

  28. κF’ κF = κF’ SM

  29. Gauge vs Yukawa -π/4 < α < +π/4 0.1 < tanβ < 100 Singlet Model 2HDM (Type-I) Georgi-Machacek Model [ξ = 2*Sqrt(6)/3]

  30. Tau vs Bottom -π/4 < α < +π/4 0.1 < tanβ < 100 Singlet 2HDM (Type-I) Georgi-Machacek Model 2HDM (Type-II) 2HDM (Type-X) 2HDM (Type-Y)

  31. Contents • Introduction • - Bottom up approach (Indirect search) • Deviations in the Higgs boson couplings in various Higgs sectors • - The hVV and hff couplings at the tree level • Higgs boson couplings in the 2HDMs • - Tree level • - One-loop level S. Kanemura, M. Kikuchi, KY, appear in PLB, arXiv: 1401.0515 [hep-ph] • Summery

  32. 2HDMs In general, Yukawa Lagrangian is given by To avoid the tree level FCNC, one of the Yukawa couplings should be forbidden. Z2 symmetry (softly-broken) Glashow, Weinberg, PRD15 (1977) Z2 symmetry (unbroken) Barbieri, Hall, Rychkov, PRD74 (2006) S3 symmetry Kajiyama, Okada, KY, arXiv:1309.6234 [hep-ph] U(1) symmetry Ko, Omura, Yu, JHEP1201 (2012) …

  33. 2HDMs with the softly-broken Z2sym. In general, Yukawa Lagrangian is given by To avoid the tree level FCNC, one of the Yukawa couplings should be forbidden. Z2 symmetry (softly-broken) Glashow, Weinberg, PRD15 (1977) Z2 symmetry (unbroken) Barbieri, Hall, Rychkov, PRD74 (2006) S3 symmetry Kajiyama, Okada, KY, arXiv:1309.6234 [hep-ph] U(1) symmetry Ko, Omura, Yu, JHEP1201 (2012) … There are four independent types of Yukawa interactions.

  34. Four Yukawa Interactions Φ２ Φ１ Φ２ • u u e e d d Φ２ Φ２ Φ１ u e u e d Φ１ d Under the Z2 symmetry, two doublets are transformed as Φ1→ +Φ1 and Φ2→ -Φ2. Type-I • Type-II (MSSM) • Barger, Hewett, Phillips (1990), Grossman (1994) • Aoki, Kanemura, Tsumura, KY (2008) Type-X (Leptophilic) Type-Y (Flipped)

  35. Mass Eigenstates In the Higgs basis, two doublets can be parameterized as: tanβ = <Φ2>/<Φ1> Charged Higgs NG bosons CP-even Higgs CP-odd Higgs SM-like Higgs boson w/126 GeV

  36. Yukawa/Gauge Interaction V f h h f V = (SM) × sin(β-α) = (SM) × [sin(β-α)+ξfcos(β-α)]

  37. Higgs Potential • The Higgs potential under the softly-broken Z2 sym. and CP-invariance • We have 8 parameters in the potential. They can be interpreted by v (=246 GeV), mh (=126 GeV), mH, mA, mH+, sin(β-α), tanβ, and M2 • Mass formulae with sin(β-α) ~1 mh2 ~ λv2, mΦ2 ~ M2 + λv2

  38. SM-like/Decoupling Limit • SM-like limit: taking sin(β-α) → 1 All the Higgs boson couplings become the same value as in the SM Higgs couplings at the tree level. • Decoupling limit: taking M2 (=mΦ2) → ∞ [mΦ2 ~ M2 + λv2] Decoupling limit can be taken only when the SM-like limit is taken.

  39. Decoupling/SM-like Limit 10% dev. cos(β-α) > 0 Excluded by unitarity cos(β-α) < 0 1% dev. δ = 0.1% dev. (mH= mA= mH+= M =)

  40. Decoupling/SM-like Limit 10% dev. cos(β-α) > 0 Excluded by unitarity cos(β-α) < 0 1% dev. κV = sin(β-α) → 1 δ = 0.1% dev. (mH= mA= mH+= M =)

  41. Decoupling/SM-like Limit 10% dev. cos(β-α) > 0 Excluded by unitarity cos(β-α) < 0 1% dev. δ = 0.1% dev. (mH= mA= mH+= M =)

  42. Patterns of Deviation in hff Couplings tanβ cotβ • cotβ e u u e d d • tanβ • cotβ • cotβ u u e e d d • tanβ • If κV≠ 1 is found, several patterns of deviation in hff appear. = (SM) × [sin(β-α) + ξf cos(β-α)] f (SM) × [sin(β-α) + cotβcos(β-α)] (SM) × [sin(β-α) - tanβcos(β-α)] h = f (SM) × (SM) × δ = 1 - sin(β-α) Type-I Type-II For cos(β-α) > 0 cos(β-α) < 0 Type-Y ~ δ ≪ 1 Type-X

  43. Patterns of Deviation in hff Couplings tanβ cotβ • cotβ e u u e d d • tanβ • cotβ • cotβ u u e e d d • tanβ • If κV≠ 1 is found, several patterns of deviation in hff appear. = (SM) × [sin(β-α) + ξf cos(β-α)] f (SM) × [sin(β-α) + cotβcos(β-α)] (SM) × [sin(β-α) - tanβcos(β-α)] h = f (SM) × (SM) × δ = 1 - sin(β-α) Type-I Type-II For cos(β-α) > 0 cos(β-α) < 0 Type-Y ~ δ ≪ 1 Type-X

  44. Bottom vs Tau κV2 = 0.99, 0.95, (δ ~ 0.005, 0.02) cos(β-α) < 0

  45. Radiative Corrections 1-loop level How these predictions can be modified by taking into account radiative corrections? The hff and hVV couplings can be measured with O(1)% accuracy. In order to compare precision measurements, to include radiative corrections are essentially important!

  46. Radiative Corrections in the 2HDMs Hollik, Penaranda, Eur. Phys. J. C23 (2002) [in the MSSM Higgs sector] Kanemura, Kiyoura, Okada, Senaha, Yuan PLB558, (2003); Kanemura, Okada, Senaha, Yuan, PRD70 (2004). hhh hVV Kanemura, Okada, Senaha, Yuan, PRD70 (2004). hff Guasch, Hollik, Penaranda, PLB515 (2001) [in the MSSM Higgs sector] We discuss 1-loop corrections to the hff couplings in the four types of the 2HDM. • There are papers for 1-loop corrections to the Higgs boson couplings in 2HDMs.

  47. Decoupling/Nondecoupling Decoupling theorem Appelquist, Carazzone (1975) 1/Mn→ 0 (M → ∞) SM SM NP+SM SM M → ∞ Violation of the decoupling theorem SM SM SM SM • If a particle mass is (mostly) given by the Higgs VEV, the particle loop effect does not vanish even in rather large mass case. E.g., Top mass：mt= ytv Scalar boson mass：mφ2 = λv2 + M2 (with λv2 > M2 ) • NP loop effects to the low energy obs. vanish when new particles are heavy.

  48. The hhh coupling @1-loop in the 2HDM Φ = H, A, H± Kanemura, Kiyoura, Okada, Senaha, Yuan PLB558 (2003)

  49. The hhh coupling @1-loop in the 2HDM Φ = H, A, H± Kanemura, Kiyoura, Okada, Senaha, Yuan PLB558 (2003) 0 In the case with M2 >> λv2, we can see the decoupling behavior.

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