270 likes | 377 Vues
M.J. Ramsey-Musolf Wisconsin-Madison. Baryogenesis and Higgs Phenomenology. Higgs Phenomenology. Baryogenesis. V. Cirigliano LANL C. Lee LBL S. Tulin Caltech S. Profumo UC Santa Cruz G. Shaugnessy Wisconsin. V. Barger Wisconsin P. Langacker IAS M. McCaskey Wisconsin
E N D
M.J. Ramsey-Musolf Wisconsin-Madison Baryogenesis and Higgs Phenomenology Higgs Phenomenology Baryogenesis V. Cirigliano LANL C. Lee LBL S. Tulin Caltech S. Profumo UC Santa Cruz G. Shaugnessy Wisconsin V. Barger Wisconsin P. Langacker IAS M. McCaskey Wisconsin D. O’Connell IAS S. Profumo UC Santa Cruz G. Shaugnessy Wisconsin M. Wise Caltech PRD 71: 075010 (2005) PRD 73: 115009 (2006) JHEP 0607:002 (2006 ) JHEP 0807:010 (2007) PRD 75: 037701 (2007) arXiv: 0706.4311 hep-ph
No need for light RH stop 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
Outline EWB & Higgs: Brief Review Extending the Higgs Sector: the simplest xSM Phenomenology: EWPO & Colliders
Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics Topological transitions Broken phase 1st order phase transition Sakharov, 1967 • Is it viable? • Can experiment constrain it? • How reliably can we compute it? EW Baryogenesis: Testability Unbroken phase CP Violation
Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics Topological transitions Broken phase 1st order phase transition More Higgs? Sakharov, 1967 Barger,Langacker, McCaskey,O.Connell,Profumo, R-M, Shaugnessy, Tulin, Wise • Is it viable? • Can experiment constrain it? • How reliably can we compute it? Baryogenesis: New Electroweak Physics 90’s: Cohen, Kaplan, NelsonJoyce, Prokopec, Turok Unbroken phase CP Violation Theoretical Issues: Strength of phase transition (Higgs sector) Bubble dynamics (expansion rate) Transport at phase boundary (non-eq QFT) EDMs: many-body physics & QCD
Light RH stop w/ special Need 1st order 2nd order So that Gsphaleron is not too fast Increasing mh Computed ESM! mH < 40 GeV Stop loops in VEff mh>114.4 GeV EMSSM ~ 10 ESM !mH < 120 GeV or ~ 90 GeV (SUSY) Electroweak Phase Transition & Higgs LEP EWWG
sin2q Need 1st order 2nd order Non-SU(2) Higgs (w / wo SUSY) So that Gsphaleron is not too fast Mixing Decay Increasing mH Computed ESM! mH < 40 GeV mh>114.4 GeV or ~ 90 GeV (SUSY) Electroweak Phase Transition & Higgs LEP EWWG
Reduced SM Higgs branching ratios mH B.R. reduction Need 1st order 2nd order Non-SU(2) Higgs (w / wo SUSY) Unusual final states So that Gsphaleron is not too fast O’Connell, R-M, Wise Mixing Decay Increasing mH Computed ESM! mH < 40 GeV mh>114.4 GeV or ~ 90 GeV (SUSY) Electroweak Phase Transition & Higgs LEP EWWG
S0 , S+, S- Extending the Higgs Sector Ando, Barger, Langacker, Profumo, R-M, Shaugnessy, Tulin SUSY Beyond the MSSM + L soft GUTs: SU(5) example Fileviez Perez, Patel, R-M
Simplest extension of the SM scalar sector: add one real scalar S H-S Mixing H1!H2H2 • Goal: identify generic features of models with extended scalar sectors that give a strong, 1st order EWPT • Determine low-energy phenomenology (Higgs studies, precision ewk) • Address CPV with a different mechanism Independent Parameters: v0, x0, l0, a1, a2, b3, b4 The Simplest Extension Model
Stable S (dark matter?) • Tree-level Z2 symmetry: a1=b3=0 to prevent s-h mixing and one-loop shh • x0 =0 to prevent h-s mixing Mass matrix The Simplest Extension, Cont’d
What is the pattern of symmetry breaking ? • What are conditions on the couplings in V(H,S) so that <H0>/T > 1 at TC ? • Compute Veff ( f, a, T ) • Minimize w.r.t f , a • Find TC • Evaluate v(TC )/TC ~ cos a(TC) f(TC )/TC CylindricalCo-ordinates Finite Temperature Potential
Analytic Numerical Analytic Electroweak Symmetry Breaking Strong first order EWPT Potential Conditions
Symmetry Breaking Two Cases for <S>at high T: Vmin = 0 Vmin = V0 < 0
Increase e Large e < 0 Reduce l Nonzero V0 Electroweak Symmetry Breaking Strong first order EWPT Potential parameters Small ac limit
x0 > 0 occurs readily Light: all models Black: LEP allowed Electroweak Symmetry Breaking Strong first order EWPT a1<0, a2 either sign a1=b3= 0, a2 < 0
Electroweak Symmetry Breaking Critical Temperature LEP allowed models: TC ~ 100 GeV |V0| / TC4 << 1
SM: global fit favors light scalar (mh~ 85 GeV) Phenomenology Electroweak Precision Observables (EWPO) Oblique parameters Similar for S,U…
Phenomenology Electroweak Precision Observables (EWPO) Oblique parameters Global fit (GAPP)
ILC: H’strahlung LHC exotic final states: 4b-jets, gg + 2 b-jets… LHC: reduced BR(h SM) m2 > 2 m1 m1 > 2 m2 EWPO compatible Phenomenology Colliders EWPO: favors light SM-like scalar
LHC: reduced BR(h SM) m1 > 2 m2 Small q: Phenomenology Colliders Z2 Symmetry
LHC Higgs Searches CMS & ATLAS: gg!H, H!gg, H!ZZ!llll H!WW!ln ln CMS : WW!H, H!gg, H!tt!l + jH!WW!ln + jj ATLAS : gg!H, H!ZZ!ll nn , Higgstrahlung CMS 30 fb-1 LHC Phenomenology Barger, Langacker, McCaskey, R-M, Shaughnessy Discovery Potential
SM-like SM-like w/ H2!H1H1 or Singlet-like SM-like Singlet-like ~ EWB Viable Could discovery heavy H2 CMS 30 fb-1 LHC Phenomenology Barger, Langacker, McCaskey, R-M, Shaughnessy Discovery Potential
SM-like SM-like w/ H2!H1H1 or Singlet-like Enhanced gHVV coupling needed for 5s observation ~ EWB Viable LHC Phenomenology, cont’d Barger, Langacker, McKaskey, R-M, Shaughnessy Determining x
Colliders: e+e- Z * h sin2q ILC Phenomenology (also WWF, ZZF)
No need for light RH stop 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