April 3, 2003 LCWS Amsterdam, 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

April 3, 2003 LCWS Amsterdam, Katri Huitu 2

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.

April 3, 2003 LCWS Amsterdam, Katri Huitu 3

ZZH coupling

• gets contribution from any nonsinglet VEV

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

02

322 )'( ii

iiZZH HvTZZggL

ZHZff

Lagrangian:

April 3, 2003 LCWS Amsterdam, Katri Huitu 4

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)

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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 (T3i

2 )

C 1 BSM Physics

Parametrize the ZZH coupling: ZZH

gmcL i

W

ZiZZH i

0

cos

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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:

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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.

April 3, 2003 LCWS Amsterdam, Katri Huitu 8

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

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Higgs mixing with radions

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,

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.

April 3, 2003 LCWS Amsterdam, Katri Huitu 10

Curvature-Higgs mixing

/ ,

, 6

2

1 61

2

1 222

v vH

Hv

HmHmL H

Diagonalize

2223622

2122tan 612612

,sin6coscos6sin

sincos

mRZHm

HmRZRZ

RZRZM

and

,1''

HMRZH

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

April 3, 2003 LCWS Amsterdam, Katri Huitu 11

positivity of kinetic terms: ,1/41

12

1/411

12

1 22

6.67.6 :TeV 10

59.075.0 :TeV 1

' ' 21111222

2

MMHMMVV

v

mL V

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

2

2

22

21112

1222 611 RZ

MMMMC

April 3, 2003 LCWS Amsterdam, Katri Huitu 12

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unitarity bounds

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

constant C curves

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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

April 3, 2003 LCWS Amsterdam, Katri Huitu 15

/ ;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

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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:

April 3, 2003 LCWS Amsterdam, Katri Huitu 17

April 3, 2003 LCWS Amsterdam, Katri Huitu 18

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