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Baryogenesis and Higgs Phenomenology. M.J. Ramsey-Musolf Wisconsin-Madison. NPAC. Theoretical Nuclear, Particle, Astrophysics & Cosmology. http://www.physics.wisc.edu/groups/particle-theory/. NCU & NTHU Seminar, June 2008. Cosmic Energy Budget. Dark Matter.
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Baryogenesis and Higgs Phenomenology M.J. Ramsey-Musolf Wisconsin-Madison NPAC Theoretical Nuclear, Particle, Astrophysics & Cosmology http://www.physics.wisc.edu/groups/particle-theory/ NCU & NTHU Seminar, June 2008
Cosmic Energy Budget Dark Matter Leptogenesis: discover the ingredients: LN- & CP-violation in neutrinos Dark Energy Baryons Baryogenesis & EDMS Higgs Phenomenology V. Barger Wisconsin P. Fileviez-Perez Wisconsin H. Patel Wisconsin P. Langacker IAS M. McCaskey Wisconsin D. O’Connell IAS G. Shaugnessy Wisconsin K. Wang Wisconsin M. Wise Caltech V. Cirigliano LANL C. Lee LBL C. Liu Wisconsin W. Haxton Washington S. Tulin Caltech S. Profumo UC Santa Cruz G. Shaugnessy Wisconsin Weak scale baryogenesis: test experimentally: EDMs & Higgs Boson Searches What are the quantitative implications of new EDM experiments for explaining the origin of the baryonic component of the Universe ? What are the implications of Higgs searches at LHC and Higgs studies at ILC for explaining the baryon asymmetry ? Explaining non-zero rB requires CP-violation and a scalar sector beyond those of the Standard Model (assuming inflation set rB=0) PRD 71: 075010 (2005) PRD 73: 115009 (2006) JHEP 0607:002 (2006 ) JHEP 0807:010 (2007) PRC 76: 035503 (2007) PRD 75: 037701 (2007) JHEP 0807:010 (2007)PRD 77: 035005 (2008) What is the origin of baryonic matter ?
Outline Baryogenesis: General Features Probing EW phase transition w/ Higgs boson phenomenology Computing YB systematically: progress & challenges Illustrative phenomenology in MSSM: EDMs, DM, & Colliders • 3 models: Real Singlet, Complex Singlet, Real Triplet
Baryogenesis: Myths • EW baryogenesis requires a light SUSY Higgs boson (mH < 120 GeV) • EW baryogenesis requires SUSY with a light RH stop • EDMs have nearly killed EW baryogenesis • Leptogenesis is the most viable option
Anomalous B-violating processes Sakharov Criteria • B violation • C & CP violation • Nonequilibrium dynamics Prevent washout by inverse processes Sakharov, 1967 Baryogenesis: Ingredients
Cosmic Energy Budget Electroweak symmetry breaking: Higgs ? Leptogenesis: discover the ingredients: LN- & CP-violation in neutrinos • Baryogenesis: Sakharov • Baryon number violation • C & CP Violation • Departure from equilibrium Weak scale baryogenesis: test experimentally: EDMs & Higgs boson studies Beyond the SM SM symmetry (broken) Baryogenesis Scenarios Baryogenesis: When? CPV? SUSY? Neutrinos? ?
Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics Sakharov, 1967 Kuzmin, Rubakov, Shaposhnikov McLerran,… EW Baryogenesis: Standard Model Anomalous Processes Different vacua: D(B+L)= DNCS Sphaleron Transitions
Shaposhnikov Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics 1st order 2nd order Sakharov, 1967 • CP-violation too weak • EWPT too weak Increasing mh EW Baryogenesis: Standard Model
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? Baryogenesis: New Electroweak Physics Unbroken phase CP Violation
CKM EDMs: New CPV? • SM “background” well below new CPV expectations • New expts: 102 to 103 more sensitive • CPV needed for BAU?
EW Precision Data: 95% CL (our fit-GAPP) LEP Exclusion Non-SM Higgs(es) ? EWSB: Higgs? • SM “background” well below new CPV expectations • New expts: 102 to 103 more sensitive • CPV needed for BAU? LEPEWWG
Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics Topological transitions Broken phase More Higgs? 1st order phase transition Ando,Barger, Langacker,Profumo, R-M, Shaugnessy, Tulin, McCaskey,… Sakharov, 1967 “Gentle” departure from equilibrium & scale hierarchy • Is it viable? • Can experiment constrain it? • How reliably can we compute it? Cirigliano, Lee, R-M,Tulin,… 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 (numerical) Transport at phase boundary (non-eq QFT) EDMs: many-body physics & QCD
Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics Topological transitions Broken phase 1st order phase transition Elementary particle EDMs: N>>1 Sakharov, 1967 Many-body EDMs: • Is it viable? • Can experiment constrain it? • How reliably can we compute it? Engel,Flambaum, Haxton, Henley, Khriplovich,Liu, R-M 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
Weak Scale Baryogenesis • B violation • C & CP violation • Nonequilibrium dynamics Topological transitions Broken phase 1st order phase transition More Higgs? Sakharov, 1967 Ando,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-doublet Higgs (w / wo SUSY) • Can an augmented Higgs sector • Generate a strong 1st order EWPT ? • Allow for a heavier SM-like Higgs than in the MSSM ? • Alleviate the tension between direct Higgs search bounds and the EWPO ? • Be discovered at the LHC ? • Can its necessary characteristic probed at the LHC and a future e+e- collider ? 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-doublet 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, Wang, 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 s hh • 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 Finite Temperature Potential 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
SM: global fit favors light scalar (mh~ 85 GeV) Phenomenology: EWPO Electroweak Precision Observables (EWPO) Oblique parameters Similar for S,U…
Fix mH=114 GeV & fit S,T,U • Require • O(m1 , m2 , sinq ) - OSM • to lie inside 95% CL ellipse Phenomenology: EWPO cont’d 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 Illustrative only
LHC Higgs Searches CMS & ATLAS: ggH, Hgg, HZZllll HWWln ln CMS : WWH, Hgg, Httl + jHWWln + jj ATLAS : ggH, HZZll 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 discover heavy H2 CMS 30 fb-1 LHC Phenomenology Barger, Langacker, McCaskey, R-M, Shaughnessy Discovery Potential
Colliders: e+e- Z * h sin2q ILC Phenomenology (also WWF, ZZF)
In progress… Controls CDM& EWPT DM mass No domain walls Key features for EWPT & DM: Softly broken global U(1) Closes under renormalization SSB leading to two fields: S that mixes w/ h and A is stable (DM) Complex Singlet: EWB & DM? Barger, Langacker, McCaskey, R-M Shaugnessy
In progress… Complex Singlet: EWB & DM? Barger, Langacker, McCaskey, R-M Shaugnessy 2 controls CDM& EWPT
S0 , S+, S- In progress… Independent Parameters: v0, x0, l0, a1, a2, b4 H- Mixing H1 -> H2H2 A Model Illustration: Real Triplet Fileviez-Perez, Patel, Wang, R-M ~ ( 1, 3, 0 )
Real Triplet : Spectrum Neutral Scalars Charged Scalars Mixing
Real Triplet : Key Features parameter EWPO Mass Splitting : W, Z loops ~ 166 MeV Fermiophobic
Pure gauge x0 supressed Real Triplet : Decays Charged: x0 dependence Below WZ Threshold Above WZ Threshold
Different ratio of WW and ZZ, ttbar BRs Higgs splitting channel Real Triplet : Decays Neutral: differences with SM Higgs & a2 dependence
In progress… Promising for LHC Promising for ILC Below WZ Threshold Above WZ Threshold Real Triplet : Production Pair production dominant Assoc production suppressed; VBF TBA
a2 = 1, 0, -1 Real Triplet : LHC Significance Photon events : a2 dependence
Real Triplet : ILC Neutral: a2 dependence in r BR ratios:
Real Triplet : Summary Parameters relevant for EWPT: x0 , a1 , a2 H+ decays: x0 , a1 H2WW coupling via Br(H2->WW): a2
No need for light RH stop Scalar Sector & the EWPT • 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
Electroweak Symmetry Breaking Critical Temperature LEP allowed models: TC ~ 100 GeV |V0| / TC4 << 1
Electroweak Symmetry Breaking x0 dependence LEP allowed models: small x0 possible for trivial high T vev
No screening for transverse W, Z masses: (MW,Z )T ~ j cos a One-loop & Finite T Contributions Cylindrical Co-ordinates Coleman-Weinberg One-loop finite T Ring sum & plasma screening
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