1. Baryogenesis and Higgs Phenomenology V. CiriglianoLANL C. LeeLBL S. TulinCaltech S. ProfumoUC Santa Cruz G. ShaugnessyWisconsin PRD 71: 075010 (2005) PRD 73: 115009 (2006) JHEP 0607:002 (2006 ) JHEP 0807:010 (2007) M.J. Ramsey-Musolf Wisconsin-Madison Baryogenesis Higgs Phenomenology V. BargerWisconsin P. LangackerIAS M. McCaskeyWisconsin D. O’ConnellIAS S. ProfumoUC Santa Cruz G. ShaugnessyWisconsin M. WiseCaltech PRD 75: 037701 (2007) arXiv: 0706.4311 hep-ph

2. Key Ideas & Results Simple extensions of the SM scalar sector (xSM) w/ small number of d.o.f. can readily lead to a strong, 1st order EWPT as needed for EW baryogenesis EWPT viable xSM can allow for heavier SM- like Higgs consistent with EWPO EWPT xSM can readily probed at the LHC and ILC using Higgs boson searches One can obtain an analytic criteria for parameters of xSM needed for 1st order EWPT that provides guidance for specific model realizations No need for light RH stop

3. Outline I.EWB & Higgs: Brief Review II.Extending the Higgs Sector: the simplest xSM III.Phenomenology: EWPO & Colliders

4. EW Baryogenesis: Testability Weak Scale Baryogenesis B violation C & CP violation Nonequilibrium dynamics Sakharov, 1967 Unbroken phase Broken phase CP Violation Topological transitions 1st order phase transition Is it viable? Can experiment constrain it? How reliably can we compute it?

5. Baryogenesis: New Electroweak Physics Weak Scale Baryogenesis B violation C & CP violation Nonequilibrium dynamics Sakharov, 1967 Unbroken phase Broken phase CP Violation Topological transitions 1st order phase transition Is it viable? Can experiment constrain it? How reliably can we compute it? 90’s: Cohen, Kaplan, Nelson Joyce, Prokopec, Turok Theoretical Issues: Strength of phase transition (Higgs sector) Bubble dynamics (expansion rate) Transport at phase boundary (non-eq QFT) EDMs: many-body physics & QCD More Higgs? Barger,Langacker, McCaskey,O.Connell, Profumo, R-M, Shaugnessy, Tulin, Wise

6. Electroweak Phase Transition & Higgs 1st order2nd order LEP EWWG Increasing m h m h >114.4 GeV or ~ 90 GeV (SUSY) Computed E SM ! m H < 40 GeV Need So that  sphaleron is not too fast E MSSM ~ 10 E SM ! m H < 120 GeV Stop loops in V Eff Light RH stop w/ special

7. Electroweak Phase Transition & Higgs Increasing m H 1st order2nd order LEP EWWG m h >114.4 GeV or ~ 90 GeV (SUSY) Computed E SM ! m H < 40 GeV Need So that  sphaleron is not too fast Non-SU(2) Higgs (w / wo SUSY) MixingDecay sin 2 

8. Electroweak Phase Transition & Higgs Increasing m H 1st order2nd order LEP EWWG m h >114.4 GeV or ~ 90 GeV (SUSY) Computed E SM ! m H < 40 GeV Need So that  sphaleron is not too fast Non-SU(2) Higgs (w / wo SUSY) MixingDecay B.R. reduction Reduced SM Higgs branching ratios Unusual final states mHmH O’Connell, R-M, Wise

9. Extending the Higgs Sector GUTs: SU(5) example + L soft SUSY Beyond the MSSM       Fileviez Perez, Patel, R-M Ando, Barger, Langacker, Profumo, R-M, Shaugnessy, Tulin

10. The Simplest Extension Model Independent Parameters: v 0, x 0, 0, a 1, a 2, b 3, b 4 H-S MixingH1!H2H2H1!H2H2 Simplest extension of the SM scalar sector: add one real scalar S Goal: identify generic features of models with extended scalar sectors that give a strong, 1 st order EWPT Determine low-energy phenomenology (Higgs studies, precision ewk) Address CPV with a different mechanism

11. The Simplest Extension, Cont’d Mass matrix Stable S (dark matter?) Tree-level Z 2 symmetry: a 1 =b 3 =0 to prevent s-h mixing and one-loop s hh x 0 =0 to prevent h-s mixing

12. Finite Temperature Potential What is the pattern of symmetry breaking ? What are conditions on the couplings in V(H,S) so that /T > 1 at T C ? Cylindrical Co-ordinates Compute V eff (  T ) Minimize w.r.t  Find T C Evaluate v(T C )/T C ~ cos  (T C )  (T C )/T C

13. Electroweak Symmetry Breaking Strong first order EWPT Potential Conditions Analytic Numerical

14. Symmetry Breaking Two Cases for at high T: V min = 0 V min = V 0 < 0

15. Electroweak Symmetry Breaking Strong first order EWPT Potential parameters Small  c limit Increase  Large e < 0 Reduce Nonzero V 0

16. Electroweak Symmetry Breaking Strong first order EWPT a 1 <0, a 2 either sign a 1 =b 3 = 0, a 2 < 0 x 0 > 0 occurs readily Light: all models Black: LEP allowed

17. Electroweak Symmetry Breaking Critical Temperature LEP allowed models: T C ~ 100 GeV |V 0 | / T C 4 << 1

18. Phenomenology Electroweak Precision Observables (EWPO) Oblique parameters Similar for S,U… SM: global fit favors light scalar (m h ~ 85 GeV)

19. Phenomenology Electroweak Precision Observables (EWPO) Oblique parameters Global fit (GAPP)

20. Phenomenology Colliders EWPO: favors light SM-like scalar EWPO compatible m 2 > 2 m 1 m 1 > 2 m 2 LHC exotic final states: 4b-jets,  + 2 b-jets… LHC: reduced BR(h SM) ILC: H’strahlung

21. Phenomenology Colliders Z 2 Symmetry m 1 > 2 m 2 LHC: reduced BR(h SM) Small  :

22. LHC Phenomenology Discovery Potential Barger, Langacker, McCaskey, R-M, Shaughnessy LHC Higgs Searches CMS & ATLAS: gg!H, H!  H!ZZ! llll  H!WW! l  l CMS : WW!H, H!  H!  ! l + j H!WW! l  jj ATLAS : gg!H, H!ZZ! ll  Higgstrahlung CMS 30 fb -1

23. LHC Phenomenology Discovery Potential  SM-like Singlet-like ~ EWB Viable Barger, Langacker, McCaskey, R-M, Shaughnessy SM-like SM-like w/ H 2 !H 1 H 1 or Singlet-like CMS 30 fb -1 Could discovery heavy H 2

24. LHC Phenomenology, cont’d Determining  Barger, Langacker, McKaskey, R- M, Shaughnessy SM-like SM-like w/ H 2 !H 1 H 1 or Singlet-like ~ EWB Viable Enhanced g HVV coupling needed for 5  observation

25. ILC Phenomenology Colliders: e + e - Z * h (also WWF, ZZF) sin 2 

26. Key Ideas & Results Simple extensions of the SM scalar sector (xSM) w/ small number of d.o.f. can readily lead to a strong, 1st order EWPT as needed for EW baryogenesis EWPT viable xSM can allow for heavier SM- like Higgs consistent with EWPO EWPT xSM can readily probed at the LHC and ILC using Higgs boson searches One can obtain an analytic criteria for parameters of xSM needed for 1st order EWPT that provides guidance for specific model realizations No need for light RH stop

27. Back Matter