A complex 2HDM at the LHC. Rui Santos

Transcription

1 A complex 2HDM at the LHC HPNP University of Toyama 11 February 2015 Rui Santos ISEL & CFTC (Lisbon) D. Fontes, J. Romão and J.P. Silva

2 The C2HDM

3 CP-conserving and explicit CP-violating - m 2 12 and λ 5 real, vacuum configuration (CP-conserving) φ 1 = 1 # 0& % (; φ 2 = 1 # 0 & % ( 2 $ ' 2 $ ' v 1 v 2 7 free parameters + M W : - m 2 12 and λ 5 complex, vacuum configuration (explicit CP-violating) φ 1 = 1 # 0& % (; φ 2 = 1 # 0 & % ( 2 $ ' 2 $ ' v 1 v 2 I. Ginzburg, M. Krawczyk and P. Osland, hep-ph/ free parameters + M W :

4 Common features tanβ = v 2 v 1 ratio of vacuum expectation values Extending the Z 2 symmetry to the fermions 4 independent Yukawa Lagrangians III = I = Y = Flipped IV = II = X = Leptonic same charged Higgs-fermions couplings three neutral scalars

5 2HDM Lagrangian (CP conserving to CP-violating potential) scalars-gauge bosons couplings g SM sin(β α) g SM (c β R 11 + s β R 12 ) = g SM cos(α 2 )cos(β α 1 ) CP-conserving to CP-violating Yukawa couplings C c β R 11 + s β R 12 sinα tanβ CP-conserving I II Y X " $ R = $ $ # c 1 c 2 s 1 c 2 s 2 (c 1 s 2 s 3 + s 1 c 3 ) c 1 c 3 s 1 s 2 s 3 c 2 s 3 c 1 s 2 c 3 + s 1 s 3 (c 1 s 3 + s 1 s 2 c 3 ) c 2 s 3 % ' ' ' & to CP-violating (h 1 couplings) α 1 = α + π / 2

6 Parametrisation (8) W. Khater and P. Osland, Nucl. Phys. B 661, 209 (2003). 2 charged, H ±, and 3 neutral, h 1, h 2 and h 3 3 masses 3 angles 2 Re[ m 12 ] real part of the soft breaking term ratio of vacuum expectation values

7 There are 3 neutral scalars. The CP nature of h 1 is determined by s 2 g CPV = g CPC = g SM cos(β α 1 ) but we can still have CP-violation (the two heavier scalars can mix). However if α 2 = 0; β α 1 = 0 R 11 = c β ; R 12 = s β ; R 13 = 0 that is, the h 1 WW vertex is the SM one g CPV = g SM cos(α 2 )cos(β α 1 ) = g SM the model is CP-conserving. Grzadkowski, Ogreid, Osland, 2014.

8 The Scan

9 Experimental constraints on the charged Higgs mass LEP ee H H + + Any (Type LS) B factories H - Hermann, Misiak, Steinhauser (2012) Models II and Y Best available bound on the charged Higgs mass

10 Experimental (LHC) pp t t b bw + H ATLAS-CONF m b tanβ m t tanβ Lauri Wendland talk AT Charged2014 Corrected for BR(H τν ) m H + = 90 GeV I II F LS tanβ

11 Experimental constraints on the charged Higgs mass vs. tanβ How the ATLAS exclusion plot would look like in types I and LS Deschamps, Descotes-Genon, Monteil, Niess, T Jampens, Tisserand, small tanβ excluded for this mass region

12 Scan Set m h1 = 125 GeV. Generate random values for potential s parameters such that, Impose pre-lhc experimental constraints, Impose theoretical constraints: perturbative unitarity, potential bounded from below.

13 Results and predictions Calculate all branching ratios and production rates at the LHC µ XX = σ2 HDM ( pp h) BR 2HDM (h XX) σ SM ( pp h) BR SM (h XX) Ask for µ WW, µ ZZ, µ γγ, µ ττ to be within 5, 10 and 20 % of the SM predictions ATLAS, ; CMS, ; S. Dawson et al,

14 Before and after the LHC (10%) Rates within 10% of the SM predictions.

15 First studies on the C2HDM with LHC data Barroso, Ferreira, RS, Silva (2012). Plot from: D. Fontes, J.C. Romão, J.P. Silva, JHEP 1412 (2014) 043. s 2 < 0.1 green 0.45 < s 2 < 0.55 blue s 2 > 0.83 red

16 Results after run 1 α 1 vs. α 2 for Type I and Type II. The rates are taken to be within 20% of the SM predictions. The colours are superimposed; cyan for μ VV, blue for μ ττ and red for μ γγ.

17 tanβ as a function of R 11, R 12 and R 13 for Type I and Type II. Same colour code. Results after run 1

18 The zero scalar scenarios There is only one way to make the pseudoscalar component to vanish R 13 = 0 s 2 = 0 and they all vanish (for all types and all fermions). There are two ways of making the scalar component to vanish R 11 = 0 c 1 c 2 = 0 c 2 = 0 g h1vv = 0 excluded R 12 = 0 s 1 c 2 = 0 excluded c 1 = 0 allowed

19 The zero scalar scenarios So, taking c 1 = 0 R 11 = 0 and a 2 U = c 2 2 s ; b 2 2 U = s 2 2 β t ; C 2 = s β c 2 β Type I a U = a D = a L = c 2 s β b U = b D = b L = s 2 t β Type II a D = a L = 0 Type F a D = 0 Type LS a L = 0 b D = b L = s 2 t β b D = s 2 t β b L = s 2 t β Even if the CP-violating parameter is small, large tanβ can lead to large values of b.

20 The zero scalar scenarios In Type II, if a D 0 b D 1 and the remaining h 1 couplings to up-type quarks and gauge bosons are " $ # % $ a U 2 = (1 s 2 4 ) = (1 1/ t β 4 ) b U 2 = s 2 4 =1/ t β 4 C 2 = t 2 β 1 t 2 β 1 = 1 s s 2 This means that the h 1 couplings to up-type quarks and to gauge bosons have to be very close to the SM Higgs ones.

21 Results after run 1 Plot from: D. Fontes, J.C. Romão, J.P. Silva, JHEP 1412 (2014) 043. CP-conserving 2HDM 1. Why the shape? Shape comes primarily from μ VV 1. Assuming that the cross section is gluon fusion via top Γ T Γ (h bb ) µ VV κ V 2 κ U 2 κ D 2 µ VV sin2 (β α) tan 2 α tan 2 β 1. Once you impose μ VV you are nearly there Fontes, Romão, Silva, Ferreira, Haber, RS, Silva, 2012.

22 Results after run 1 for the CP-conserving case sin(β - α) = 1 sin(β + α) = 1 The SM-like limit (alignment) all tree-level couplings to fermions and massive gauge bosons are the SM ones. κ i = g 2 HDM g SM at tree-level κ 2 i = Γ 2 HDM (h i) Γ SM (h i) sin(β α) =1 κ F =1; κ V =1 Wrong-sign limit κ D κ V < 0 or κ U κ V < 0 κ D = sinα = sin(β + α) + cos(β + α)tanβ κ cosβ sin(β + α) =1 κ D = 1 (κ U =1) Ginzburg, Krawczyk, Osland 2001 Ferreira, Gunion, Haber, RS 2014 Ferreira, Guedes, Sampaio, RS 2014 U = cosα sinβ = sin(β + α) + cos(β + α)cot β sin(β α) = tan2 β 1 tan 2 β +1 κ V 0 if tanβ 1

23 Results after run 1 No major differences relative to the CP-conserving case SM-like limit sin(β - α) = 1 sin(β + α) = 1 tanβ as a function of sin(α 1 π/2) for Type I, Type II and LS. Full range (cyan), s 2 < 0.1 (blue) and s 2 < 0.05 (red).

24 The wrong-sign limit sin(β + α) = 1 The future at the LHC The pseudoscalar limit scenario. The SM-like limit sin(β - α) = 1 The CPconserving line limit sin(α 2 ) = 0 Left: sgn(c) b D (or b L ) as a function of sgn(c) a D (or a L ) for Type II, 13 TeV, with rates at 10% (blue), 5% (red) and 1% (cyan) of the SM prediction. Right: same but for up-type quarks.

25 NO wrong-sign limit The future at the LHC SM-like limit Plot from: Boudjema, Godbole, Guadagnoli, Mohan, Left: sgn(c) b U as a function of sgn(c) a U for Type I, 13 TeV, with rates at 10% (blue) and 5% (red) of the SM prediction. Right: same but for leptons and LS.

26 EDMs Plot from: Brod, Haisch, Zupan, JHEP 1311 (2013) See also Inoue, Ramsey-Musolf, Zhang, 2014 Cheung, Lee, Senaha, Tseng, 2014

27 Direct probing at the LHC For the C2HDM we need three independent measurements tanφ i = b i a i ; i =U, D, L Just one measurement for type I (U=D=L), two for the other three types. At the moment there are studies for tth and ττh. If Φ t Φ τ type I and F are excluded. To probe model F we need the bbh vertex.

28 Direct probing at the LHC (tth) pp jjh Hankele, Klamke, Zeppenfeld 2006 Corresponds to the C2HDM in the limit cos(β α 1 ) = 0; tan β =1 In this case φ t = α 2 " $ # %$ φ t < 40º 50 fb 1 φ t < 25º 300 fb 1 Plot from: Dolan, Harris, Jankowiak, Spannowsky, PRD90, (2014).

29 Limits on Φ t based on the rates only Φ t = Φ U rates at 20% (green), 5% (red) Competitive for Type I but not for Type II

30 Direct probing at the LHC (ττh) pp h τ + τ Berge, Bernreuther, Ziethe 2008 Berge, Bernreuther, Niepelt, Spiesberger, 2011 Berge, Bernreuther, Kirchner 2014 A measurement of the angle tanφ τ = b L a L can be performed with the accuracies tanφ τ = s β c 1 tanα 2 tanα 2 = c 1 s β tanφ τ # % $ &% Δφ τ = 40º 150 fb 1 Δφ τ = 25º 500 fb 1 Numbers from: Berge, Bernreuther, Kirchner, EPJC74, (2014) 11, It is not a measurement of the CP-violating angle α 2.

31 Direct probing at the LHC The zero scalar limit SM-like limit Left: tanβ as a function of sinα 2 for Type II, 13 TeV, with all rates at 10% (blue); a D < 0.1 b D -1 < 0.1 (green); b D < 0.05 a D -1 < 0.05 (red). Right: same with tanβ replaced by cosα 1

32 Direct probing at the LHC The zero scalar limit SM-like limit Φ τ = Φ D Φ τ = Φ D Left: cosα 1 as a function of Φ D for Type II, 13 TeV, with all rates at 10% (blue); a D < 0.1 b D -1 < 0.1 (green); b D < 0.05 a D -1 < 0.05 (red). Right: same with tanβ replaced by sgn(c) a D.

33 Conclusions We have discussed a CP-violating 2HDM. In all types except Type I there is almost no restriction to the ratio of pseudoscalar to scalar components of the Yukawa couplings for down-type quarks and leptons. We have shown that a measurement of the rates only, have little impact on probing zero scalar component scenarios. We need to go to about 1% accuracy to probe the scalar zero component scenario in type II. There are several proposals for direct measurements of the pseudoscalar to scalar ratio at the next LHC run in tth and ττh. Only a direct study of the hbb vertex will allow to probe the Flipped model.

34 The CP-conserving 2HDM Surprises in h-> γγ? 1. wrong sign and non-decoupling Ferreira, Gunion, Haber, RS 2014 Ferreira, Guedes, Sampaio, RS 2014

35 If we were only considering the gauge bosons and fermion loops we should find points at 5 % for the wrong-sign scenario. In fact, if the charged Higgs loops were absent, changing the sign of κ D would imply a change in κ γ of less than 1 %. The relative negative values (and almost constant) contribution from the charged Higgs loops forces the wrong sign μ γγ to be below 1.

36 VV and γγ within 5 % of the SM predictions. 1. A measurement of the rates at 5% will exclude the wrong sign leg. 1. And in this case sin(β-α) = 1 and the 2HDM can go home If μ ττ is within 10% of the SM prediction, large values of tanβ are excluded.

37 1. 5% would exclude the wrong sign in both scenarios but also the heavy scenario in the SM-like limit due to the effect of charged Higgs loops + theoretical and experimental constraints.

38 SM-like limit (alignment) vs Decoupling Gunion, Haber (2003)

39 Heavy scenario and boundness from below 1.Alignment 1.SM-like SM g like HH 2m 2 H ± + H m H 2 2M 2 v 2 Wrong g Sign HH 2m 2 H ± + H v 2 m H 2 1.Wrong Sign Boundness from below M < m H 2 + m h 2 /tan 2 β b -> s γ 2 m H ± > 340 GeV

40 EXTRA

41 Relation between Yukawas and gauge couplings R 11 = C s 2 βa U c β ; R 12 = s β a U ; R 13 = t β b U ( ) 2 1= R R R 2 13 = C s 2 βa U c β 2 + s 2 β a 2 U + t 2 2 β b U All Types ( ) ( a U C) 2 + b 2 U = 1 C 2 t β 2 Type II ( a D C) 2 + b 2 D = t 2 ( β 1 C 2 )

42 Direct probing at the LHC (ττh) pp h τ + τ Berge, Bernreuther, Ziethe 2008 Berge, Bernreuther, Niepelt, Spiesberger, 2011 Berge, Bernreuther, Kirchner 2014 A measurement of the angle tanφ τ = b L a L can be performed with the following accuracies # % $ &% Δφ τ = 40º 150 fb 1 Δφ τ = 25º 500 fb 1 Plot from: Berge, Bernreuther, Kirchner, EPJC74, (2014) 11, 3164.