1. Oct, 2003WIN'03, Katri Huitu1 Probing the scalar sector with ZZH outline: Introduction Models: higher representations radion (nonSUSY/SUSY) Conclusions Debajyoti Choudhury, Anindya Datta, Katri Huitu, hep-ph/0302141, to appear in Nucl.Phys.B

2. Oct, 2003WIN'03, Katri Huitu2 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.

3. Oct, 2003WIN'03, Katri Huitu3 ZZH coupling gets contribution from any nonsinglet VEV ZZH coupling essential in Higgs production: or gauge boson fusion use to separate between models Lagrangian:

4. Oct, 2003WIN'03, Katri Huitu4 E.g. SU(5) GUT The SM fermions in contain neutral scalars doublets Y=1 triplet in minimal SU(5) problems with realistic spectrum  need more representations These contain singlets, triplets (Y=0,1), 4-plets (Y=3/2,1/2), 5-plets (Y=2,1,0)

5. Oct, 2003WIN'03, Katri Huitu5 A strong constraint from the  -parameter, experimentally  1. We demand  = 1. 4 max (T 3i 2 )  C  4 min (T 3i 2 ) C  1  BSM Physics Parametrize the ZZH coupling:

6. Oct, 2003WIN'03, Katri Huitu6 fermions of the SM couple to doublets  Y t increases with decreasing v 1/2 : Y t RGE: Z mass:

7. Oct, 2003WIN'03, Katri Huitu7 Triplets Added fine tuning Triplets (3,0) and (3,1)  1 < C < 4 Georgi, Machachek,NPB 262 (1985) 463.

8. Oct, 2003WIN'03, Katri Huitu8 E.g. in the Georgi – Machachek model, for the fermion widths 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.

9. Oct, 2003WIN'03, Katri Huitu9 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

10. Oct, 2003WIN'03, Katri Huitu10 Radions in RS scenario 5-dim universe, compactify on S 1 / Z 2 hidden visible y=0 y=  massless fields:    graviton  g   r c modulus T(x) T(x) has zero potential  stabilize, parameters on visible brane scaled by e -k  r c, radion     e -k  (T-r c ), m   O(1 TeV) Randall, Sundrum, PRL 83 (1999) 3370, 4690. Goldberger, Wise, PRL 83 (1999)4922, PLB475 (2000)275.

11. Oct, 2003WIN'03, Katri Huitu11 Radion couplings: Stress energy tensor: Curvature-Higgs mixing  Giudice, Rattazzi, Wells, NPB 595 (2001) 250; Csaki, Graesser, Kribs, PRD 63 (2001) 065002. mixing parameter

12. Oct, 2003WIN'03, Katri Huitu12 Diagonalize  positivity of kinetic terms:

13. Oct, 2003WIN'03, Katri Huitu13 Couplings to physical scalars (V=general gauge boson): 

14. Oct, 2003WIN'03, Katri Huitu14 unitarity bounds Han,Kribs,McElrath, PRD 64 (2001)076003 constant C curves

15. Oct, 2003WIN'03, Katri Huitu15 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 F S ): 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

16. Oct, 2003WIN'03, Katri Huitu16 Lagrangian The warp factor note: K is model dependent

17. Oct, 2003WIN'03, Katri Huitu17  Diagonalize  H 1 0,H 2 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:

18. Oct, 2003WIN'03, Katri Huitu18

19. Oct, 2003WIN'03, Katri Huitu19 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