Probing the scalar sector with ZZH

Oct, 2003 WIN'03, Katri Huitu 1

Probing the scalar sector with ZZH

outline:IntroductionModels:

higher representationsradion (nonSUSY/SUSY)

Conclusions

Debajyoti Choudhury, Anindya Datta, Katri Huitu,

hep-ph/0302141, to appear in Nucl.Phys.B


Introduction • Assume that EWSB due to Higgs mechanism• Light scalars not taking part in the EWSB can

mix with Higgs• In extensions of the Standard Model new scalars

and new representations- spontaneous CP violation, - supersymmetry, - left-right model, - gauge unification,...

• What can a detected set of scalars tell about the model?

• Related works: Burgess et al, IJMP A17(2002) 1841; Ellis et al, PLB 502 (2001) 171; Kane et al PRD 64 (2001) 095013; Ambrosanio et al NPB 624 (2002) 3.


ZZH coupling

• gets contribution from any nonsinglet VEV

• ZZH coupling essential in Higgs production: or gauge boson fusion use to separate between models

02

322 )'( ii

iiZZH HvTZZggL

ZHZff

Lagrangian:


E.g. SU(5) GUT The SM fermions in , 105 and

151055504551010455105 , ,

15455 , , contain neutral scalars

doublets

Y=1 tripletbreaking symmetry SU(5) for need 24

in minimal SU(5) problems with realistic spectrum need more representations

... ...,' ..., 35454570151524455

These contain singlets, triplets (Y=0,1), 4-plets (Y=3/2,1/2), 5-plets (Y=2,1,0)


A strong constraint from the -parameter,

i ii

i iiiii

WZ

W

vT

vTTTr

m

m22

3

223

22

2

2

])1([

cos

experimentally 1. We demand = 1.

i ii

i ii

jj vT

vTcC

223

2432 4

4 max (T3i2 ) C 4 min

(T3i2 )

C 1 BSM Physics

Parametrize the ZZH coupling:

ZZH

gmcL i

W

ZiZZH i

0

cos


fermions of the SM couple to doubletsYt increases with decreasing v1/2:

,2/1v

vyy SMSM

ff

Yt RGE:

42123

2

8

9)

12

17

4

98(

ln2

tt

t

yy

d

dy

223

222 )'( ii iZ vTggm Z mass:


Triplets Added

fine tuning

Triplets (3,0) and (3,1)

1 < C < 4

20

21

21

20

21

12

)02(21

)12(

YY

Y

YY

vv

v

vv

Georgi, Machachek,NPB 262 (1985) 463.


SMff

ffffSMSMff

ffff

v

v

expexp2

2/1

expexp

E.g. in the Georgi – Machachek model, for the fermion widths

ffSMSM

ffGM vv 2

2/1 )/(

Use the measured value and error to constrain the ratio of VEVs

For a 90 % C.L. constraint on the ratio, is 1.64, if exp has 1 limits.


Fiveplets added

(5,0) and (5,1) enhance (5,2) suppresses

(5,0) and (5,2):1 < C < 16

(5,0) and (5,1):1 < C < 12


Radions in RS scenario

5-dim universe, compactify on S1 / Z2

hidden visible

y=0 y=

22||22 dyrdxdxeds cykrc

massless fields: gravitong

rc modulus T(x)

T(x) has zero potential stabilize,

parameters on visible brane scaled by e-krc ,

radion e-k(T-rc), m O(1 TeV)

Randall, Sundrum, PRL 83 (1999) 3370, 4690.

Goldberger, Wise, PRL 83 (1999)4922, PLB475 (2000)275.


Radion couplings:

Stress energy tensor:

)(int SMTL

...)2(2

)(

2)(

22

22

HHHmFFg

g

ZZmWWmffmSMT

haa

a a

aa

ZWf

f

Curvature-Higgs mixing

Giudice, Rattazzi, Wells, NPB 595 (2001) 250;Csaki, Graesser, Kribs, PRD 63 (2001) 065002.

/ ,

, 6

2

1 61

2

1 222

v vH

Hv

HmHmL h

HHgRgxdS visvis )(4 mixing

parameter


Diagonalize

22222

222

36

122tan 6161

,sin6coscos6sin

sincos

mZm

mZZ

ZZM

Rh

hRR

RR

and

,1''

HMRZH

positivity of kinetic terms: ,1/41

12

1/411

12

1 22

6.67.6 :TeV 10

59.075.0 :TeV 1

/

,

v

vH


22

22

21112

1222 611 RZ

MMMMC

Couplings to physical scalars (V=general gauge boson):

' ' 21111222

2

MMHMMVV

v

mL V


unitarity bounds

Han,Kribs,McElrath,PRD 64 (2001)076003

constant C curves


Supersymmetric RS model

We consider

J.A. Casas, J.R. Espinosa, I. Navarro, NPB 620 (2002) 195

Supplement MSSM with a radion T and

dilaton S in the bulk (susy breaking along FS):

To make contact with the superstring theory, the RS model may need to be supersymmetrized.

Extra dimensions may be connected with the supersymmetry breaking method:

Stabilization e.g. AMSB possible.Luty, Sundrum, PRD 62 (2000) 035008


/ ;3 2

2†

tTTM

eP

TT

Lagrangianjiij DDGL

2

1

,2

ji

effij

KG

2

2 *exp ieff

eff

ttK

..|| 212 chHH

i iieff

The warp factor

ZZHvHvgv

LW

HZZ022

0112

2

2

2

cos44311

note: K is model dependent


2Z

tZZ

mZtZL

22

21

2

2/1

2

2

,4

311cos2

vvvvgv

mW

Z

2

2

2

2

22

2

2

3111622

11

8

5

2

11

21

vvvC

Diagonalize H10,H2

0,t sum of the squares of scalar couplings (normalized to SM value):

Coupling to the singlet radion from the trace of stress-energy tensor:



Conclusions

• Sum of the ZZH couplings can be an efficient separator between models

• For scalars in higher representations of SU(2)L, the parameter and perturbativity of the top Yukawa-coupling constrain C

• In higher dimensions, the Higgs-curvature mixing may effect C strongly

Documents

Probing the scalar sector with ZZH