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3.Phenomenology of Two Higgs Doublet Models

3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

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Page 1: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

3.Phenomenology of Two Higgs Doublet Models

Page 2: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Charged Higgs Bosons

• One of the most important features of all 2 HDMs is existence of

charged Higgs scalars • Yukawa couplings associated with

Page 3: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Singly charged Higgs mass limit from LEP:

Assumed decay channels

,H cs

78.6Hm GeV

LEP Higgs working group,LHWG note 2001-05.

Page 4: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

• Yukawa interactions of charged Higgs can affect various decays and mixing associated with flavors

• For large type I is fermiophobic, type X is leptophilic which could lead to a huge branching ratio for

• Those models are not constrained by rare B decays. • Large contributions to rare B decays are possible in type II,

Y should be constrained by experimental results of rare B decays

Constraints from Flavor Physics

Page 5: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Barger/Hewett/Phillips, 1990

The branching ratios can be very different from the SM.

tan b is important for phenomenology!

For processes which depend only on quark sector, models I and IV are similar, as well as models II and III.

𝐻±→𝜏±𝜈

Page 6: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

• Type II (Y) model

- the couplings of charged Higgs to t-quark and b-quark are

or

- potentially large virtual effects in b-quark decays and mixing.

- A very strong bound on come from studies of

In model II the contribution is always bigger than in the SM, while in model I one can have strong cancellations due to –cot b in the coupling.

𝐵→𝑋 𝑠𝛾

Page 7: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

V

Full NLO QCD results

Uncertainty range of theoretical predictions (Ciuchini et al, 1998) issuch that mH+>250-300 or so GeV is required in type II

Page 8: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

• Other sever constraint for type II model :

- : not a loop process but proceeds through tree-level virtual

exchange.

- severe constraints at large .

¿1.13±0.05

2006 ICHEP

Page 9: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Crivelli et al.arXiv:1303.5877

Page 10: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons
Page 11: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Bounds for type II model

(Haisch ‘08)

Page 12: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Solid line : from

Bounds for type I model

(Branco et.al ‘11)

dashed line : from

Page 13: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Productions of Charged Higgs• Light charged Higgs :

Top decay can produce light charged Higgs : t Hb

Constrained by (Tevatron)

• Production of light charged Higgs at the LHC :

BR(tH±b)~mtop2 cot2β+mb

2 tan2β

Page 14: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

108 top quarks producedMore than 105 charged Higgs ex-pected

• Heavy charged Higgs production at the LHC

dominant channel :

Via gluon fusion, ggtbH+

Page 15: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

M. Flechl., ATLAS Collaboration, presented at Prospects for Charged Higgs Discovery at Hadron Collider, Uppsala, Sweden (2008)

Page 16: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Search for light charged Higgs at the LHC

• Via decay channels - for light charged Higgs below top mass :~100 %

H± decay BR. into different final states for tan = 20

H+ Decay W Decay

,had qq

,had l

, lep qq

Page 17: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Discovery potential

CMS Note 2006/056

Page 18: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Search for heavy charged Higgs at the LHC

• Above top mass: - BR(H+tb)~0.8-1 - H+tb results in complex final states :3 or 4 b jets

• Crucial to supress very large kinematically similar ttbar+jets background

H+ Decay W Decay

,had qq

tb l & qq

xBR (pb)Channels of interest:

Page 19: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Discovery potential

with systematics

without systematics Background: FAST simul.

without systematics

ATLAS CMS

systematics included Background: Full simul.

- promising channel for heavy charged Higgs

Page 20: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Search for neutral Higgs

Page 21: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Mass spectrumsFor MA> 150 GeV (decoupling

limit)The heavy MSSM Higgs:MA≈ MH ≈MH

±

Sven HeinemeyerAtlas meeting 29.01.2008

Pythia 6.226 FeynHiggs2.2

S.G, H.Bilokon,V.Chiarella,G.NicolettiATL-PHYS-PUB-2007-001

For MA< 135 GeV (Mhmax scenario)

The ligth Higgs is SM-like

MA≈ Mh

Pythia 6.226

Page 22: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Production of neutral Higgses

• Main production mechanism ~SM• For high and moderate tanb the production with b quarks is enhanced• For mA >>mZ A/H behave very similar →decoupling region• A, H, H± cross section ~tanb2

V*=W/Z

Page 23: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Production Cross Section

=h,H,A

Abdelhak Djouadi arXiv:hep-ph/0503173v2 (2005)

• At small tanb gg→h,H,A dominant• Vector boson fusion process pp→qq→qq+WW/ZZ→qq+h/H important at m h ~ m hmax

• Higgsstrahlung neglegible

• At high tanb associated b quarks production dominates pp → bb →h/H/A+ bb

Page 24: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Branching Ratio for Neutral Higgs Decays

Production rate

• Decay bb dominates, tt lower background weaker sensitivy on SUSY parameters

2),,( fmAHh

• Decoupling region MA≥ 150 GeV tanb ≈30or MA≥ 400-500 GeV tanb=3

Abdelhak Djouadi arXiv:hep-ph/0503173v2 (2005)

Page 25: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Branching Ratio for Neutral Higgs Decays

•Decay bb, tt dominates•Decay mm possible

•Intense coupling region tanb ≈30 MA~ 120-140 GeV Coupling to W,Z up quarks suppressedCoupling down quark (b) and t enhanced

Abdelhak Djouadi arXiv:hep-ph/0503173v2 (2005)

Page 26: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Discovery Potential Signal cross section uncertainties 17% Systematic experimental uncertainties based on detector expected performances:e.g. muon efficiency, muon PT scale, muon resolution, Jet energy scale, Jet energy resolution, btag efficiency, b-tagging fake rate. Based on detector expected performance 10-20%Large systematic uncertainties demand for data-driven method background estimation

Combined 0-b-jet and 1 b-jet analysispreliminary preliminary

Page 27: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Pair ProductionsTrilinear coupling can be large for Heavy Higgs

(Robert N. Hodgkinson )

Page 28: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Pair Productions``Feasibility study of Higgs pair creation in gamma-gamma collider’’ (Norizumi Maeda )

For measuring Higgs self coupling

Higgs mass =125 GeV

Optimized photon collision E = 270 GeV

(BR=0.43)

Page 29: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Project I1. Let us consider an SU(2) gauge theory with scalar fields that

make up the triplet representation as follows:

In the theory, we require invariance under the gauge transform :

=exp) , where the exponential factor is a 3x3 matrix,

and the operator generates isospin rotations about axis and

satisfies SU(2) algebra (explicitly,

Page 30: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Project IAs usual, the covariant derivative takes the form In this theory, SU(2) gauge symmetry is spontaneously broken , and the vacuum is given by .The scalar potential of the theory is given by +We can shift the scalar fields and expand about the minimum configuration by using

Φ=𝑒𝑥𝑝[ 𝑖𝑣 (𝜁1𝑇1+𝜁2𝑇2)]( 00

𝑣+𝜂)

Page 31: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Project I(a) Show that becomes a massive Higgs scalar.(b) Obtain the mass of .(c) Show that the would-be Goldstone bosons disappear entirely.(d) Show that the vector bosons corresponding to the (broken symmetry) generators and acquire a common mass (e) Show that the gauge boson remains massless and explain why? (Hint, Exploit the gauge invariance by transforming to unitary gauge.)

Page 32: 3.Phenomenology of Two Higgs Doublet Models. Charged Higgs Bosons

Project IIFor the scalar potential of two Higgs doublet models given by

(a)Derive the minimization conditions of V (taking .(b)Show that would-be Goldstones (three) are eaten by gauge

bosons (i.e. disappear).(c)Obtain masses of 5 Higgs bosons (2 neutral CP even, 2

charged and a CP-odd).