Scalar Dark Matter and the Higgs Portal M.J. Ramsey-Musolf Wisconsin-Madison NPAC Theoretical Nuclear, Particle, Astrophysics & Cosmology SSNuDM, Shanghai, September 2012

Outline 1.Dark Matter Portals 2.Why the Higgs portal? 3.Why scalar dark matter ? 4.Simplest examples: scalar DM & LHC 5.Long-range dark forces Supersymmetry as an illustration Theoretical progress & challenges Our work

I. Dark Matter Portals Standard ModelHidden Sector (DM)

BSM Physics: EFT Framework EFT: Integrate out heavy DOF & retain only light DOF w/ M <<  Thanks: Adam Ritz

Portals Thanks: Adam Ritz

Classifying Portals “dark photons” Thanks: Adam Ritz

Classifying Portals  ! scalar DM  ! fermionic DM Mediator mass Thanks: Adam Ritz

Classifying Portals Thanks: Adam Ritz

II. Why the Higgs Portal ?

Higgs Boson Searches

SM Higgs?

SM “background” well below new CPV expectations New expts: 10 2 to 10 3 more sensitive CPV needed for BAU? LEP, Tevatron, & ATLAS Exclusion Non-SM Higgs(es) ? LHC Observation Precision Tests LHC Exclusion SM Higgs properties ?

Scalar Fields in Particle Physics Scalar fields are a simple Has a fundamental scalar finally been discovered ? Scalar fields are theoretically problematic  m 2 ~  2 If so, is it telling us anything about  ?

What is the BSM Energy Scale  ? Remarkable agreement with EWPO EWPO: data favor a “light” SM-like Higgs scalar Tension: EWPO + Direct Searches

What is the BSM Energy Scale  ? Remarkable agreement with EWPO Agreement w/ SM at ~ level: O NP = c /  2  ~ 10 TeV generically Barbieri & Strumia ‘99

Scalar Fields in Particle Physics Scalar fields are a simple Must  BSM ~ TeV to maintain a weak scale scalar ? Scalar fields are theoretically problematic  m 2 ~  2 EWPO: for new interactions coupling to gauge bosons or fermions,  BSM >> TeV

Scalar Fields in Particle Physics Scalar fields are a simple Must  BSM ~ TeV to maintain a weak scale scalar ? Scalar fields are theoretically problematic  m 2 ~  2

Scalar Fields in Particle Physics Scalar fields are a simple Must  BSM ~ TeV to maintain a weak scale scalar ? Scalar fields are theoretically problematic  m 2 ~  2 Perhaps new weak scale physics couples only to scalar sector: “Higgs portal”

III. Why scalar dark matter ?  ??

Scalar Fields & Early Universe

Scalar Fields in Cosmology What role do scalar fields play (if any) in the physics of the early universe ?

Scalar Fields in Cosmology ProblemTheoryExp’t Inflation Dark Energy Dark Matter Phase transitions

Symmetries & Cosmic History Standard Model Universe EW Symmetry Breaking: Higgs ? New Forces ? QCD: n+p! nuclei QCD: q+g! n,p… Astro: stars, galaxies,..

Symmetries & Cosmic History Standard Model Universe EW Symmetry Breaking: Higgs ? New Forces ? Puzzles the Standard Model can’t solve 1.Origin of matter 2.Unification & gravity 3.Weak scale stability 4.Neutrinos SUSY ? GUTS ? Extra Dims ? WRWR WL*WL* WLWL ~ NRNR Terascale

Scalar Fields & Inflation Standard Model Universe EW Symmetry Breaking: Higgs ? New Scalars ? QCD: n+p! nuclei QCD: q+g! n,p… Astro: stars, galaxies,.. Flatness Isotropy Homogeneity Scalar Field: Inflaton “Slow roll” Reheat

Scalar Fields & Dark Energy ?  CDM Supernovae BAO > 0 Cosmological constant ? Scalar Field: Quintessence ?

Scalar Fields & the Origin of Matter ? Baryogenesis: When? CPV? SUSY? Neutrinos? Non-equilibrium dynamics or CPT violation?

Scalar Fields & the Origin of Matter ? Baryogenesis: When? CPV? SUSY? Neutrinos? Non-equilibrium dynamics or CPT violation? Electroweak Phase Transition ? New Scalars

Scalar Fields & the Origin of Matter ? ? Darkogenesis: When? SUSY? Neutrinos? Axions ? Y B related ? Baryogenesis: When? CPV? SUSY? Neutrinos? Non-equilibrium dynamics or CPT violation? Rotation curves Lensing Bullet clusters Electroweak Phase Transition ? New Scalars

Scalar Fields & the Origin of Matter ? ? Darkogenesis: When? SUSY? Neutrinos? Axions ? Y B related ? Baryogenesis: When? CPV? SUSY? Neutrinos? Non-equilibrium dynamics or CPT violation? Rotation curves Lensing Bullet clusters Electroweak Phase Transition ? New Scalars: CDM ?

Scalar Fields in Cosmology Inflation Dark Energy Dark Matter Phase transitions ProblemTheoryExp’t     ? ? ? ?

Scalar Fields in Cosmology Inflation Dark Energy Dark Matter Phase transitions ProblemTheoryExp’t     ? ? ? ? Could experimental discovery of a fundamental scalar point to early universe scalar field dynamics?

Scalar Fields in Cosmology Inflation Dark Energy Dark Matter Phase transitions ProblemTheoryExp’t     ? ? ? ? Focus of this talk, but perhaps part of larger role of scalar fields in early universe

Electroweak Phase Transition

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSB

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSBY B : CPV & EW sphalerons

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSBY B : diffuses into interiors

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSBY B : diffuses into interiors Preserve Y B initial Quench EW sph T C, E sph, S tunnel F(  )

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSB GW Spectra:  Q &  t EW F(  ) Detonation & turbulence nMSSM QQ  t EW

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSB GW Spectra:  Q &  t EW F(  ) Detonation & turbulence

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM LHC Searches “Strong” 1 st order EWPT Bubble nucleation EWSB Detonation & turbulence

EW Phase Transition: New Scalars 1st order2nd order Increasing m h New scalars Baryogenesis Gravity Waves Scalar DM ? LHC Searches ? “Strong” 1 st order EWPT Bubble nucleation EWSB T C, E sph, S tunnel  Q &  t EW F(  ) Y B preservation, detonation & turbulence

Dark Matter:   &  SI Thermal DM: WIMP   SM Direct detection: Spin-indep DM-nucleus scattering   A A ?

IV. Simple examples

Higgs Portal: Simple Scalar Extensions ExtensionEWPTDMDOF May be low-energy remnants of UV complete theory & illustrative of generic features Real singlet Complex Singlet Real Triplet    ?    

The Simplest Extension Model Independent Parameters: v 0, x 0, 0, a 1, a 2, b 3, b 4 H-S Mixing H 1 ! H 2 H 2 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 xSM EWPT:  Signal Reduction Factor ProductionDecay Simplest extension of the SM scalar sector: add one real scalar S (SM singlet) EWPT: a 1,2 = 0 & = 0 DM: a 1 = 0 & = 0 // O’Connel, R-M, Wise; Profumo, R-M, Shaugnessy; Barger, Langacker, McCaskey, R-M Shaugnessy; He, Li, Li, Tandean, Tsai; Petraki & Kusenko; Gonderinger, Li, Patel, R-M; Cline, Laporte, Yamashita; Ham, Jeong, Oh; Espinosa, Quiros; Konstandin & Ashoorioon…

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

The Simplest Extension Model H-S Mixing H 1 ! H 2 H 2 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 xSM EWPT:  Signal Reduction Factor ProductionDecay DM Scenario

HW Question 1 Consider the real singlet extension: explain why the presence of an operator S 3 in addition to H + H S 2 would imply that S can decay to Standard Model particles

The Simplest Extension Model Independent Parameters: v 0, x 0, 0, a 1, a 2, b 3, b 4 H-S Mixing H 1 ! H 2 H 2 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 xSM EWPT:  Signal Reduction Factor ProductionDecay DM Scenario  DM &  SI ++…

DM Phenomenology Relic Density He, Li, Li, Tandean, Tsai Direct Detection He, Li, Li, Tandean, Tsai Barger, Langacker, McCaskey, R-M, Shaugnessy H S S f f - Higgs pole

LHC & Higgs Phenomenology LHC discovery potential Signal Reduction Factor ProductionDecay V 1j < 1: mixed states h j New decays: h 2 ! h 1 h 1 Dark matter: no mixing ! states are h,S New decays h! SS (invisible!) possible

LHC & Higgs Phenomenology Invisible decays He, Li, Li, Tandean, Tsai Look for azimuthal shape change of primary jets (Eboli & Zeppenfeld ‘00) Dijet azimuthal distribution  (h!SS)=0 Invis search LHC discovery potential Signal Reduction Factor ProductionDecay

LHC & Higgs Phenomenology Invisible decays He, Li, Li, Tandean, Tsai Look for azimuthal shape change of primary jets (Eboli & Zeppenfeld ‘00) Dijet azimuthal distribution LHC discovery potential Signal Reduction Factor ProductionDecay Jets + E T

VBF: Invisible Search I H ! W + W - !  jj : ideally only W decay products in central region (Chehime & Zeppenfeld ‘93)  H ! W + W - ! l + l -  : central region minijet from SM bcknd,  separation from dilepton pair (Barger, Phillips, Zeppenfeld ‘94) Central Jet Veto “Lego plot” 

VBF: Invisible Search II  Look for azimuthal shape change of primary jets (Eboli & Zeppenfeld ‘00) Dijet azimuthal distribution  p T (H) distribution Large p T (invisible decay) Cahn et al ‘87 VBF + Invis decay SM bcknd

LHC & Higgs Phenomenology Invisible decays He, Li, Li, Tandean, Tsai Look for azimuthal shape change of primary jets (Eboli & Zeppenfeld ‘00) Dijet azimuthal distribution LHC discovery potential Signal Reduction Factor ProductionDecay ATLAS

LHC & Higgs Phenomenology Giardino et al: arXiv 1207:1347

Higgs Portal: Simple Scalar Extensions ExtensionEWPTDMDOF May be low-energy remnants of UV complete theory & illustrative of generic features Real singlet Complex Singlet Real Triplet    ?    

Complex Singlet: EWB & DM? Barger, Langacker, McCaskey, R-M Shaugnessy Spontaneously & softly broken global U(1) Controls  CDM, T C, & H-S mixing Gives non-zero M A = 0

Complex Singlet: EWB & DM? Barger, Langacker, McCaskey, R-M Shaugnessy Consequences: Three scalars: h 1, h 2 : mixtures of h & S A : dark matter Phenomenology: Produce h 1, h 2 w/ reduced   Reduce BR (h j ! SM) Observation of BR (invis) Possible obs of  SI

Complex Singlet: EWB & DM Barger, Langacker, McCaskey, R-M, Shaugnessy  2 controls  CDM & EWPT M H1 = 120 GeV, M H2 =250 GeV, x 0 =100 GeV decreasing T C

Complex Singlet: Direct Detection Barger, Langacker, McCaskey, R-M, Shaugnessy Two component case (x 0 =0) Little sensitivity of scaled  SI to  

HW Question 2 Explain why the scaled direct detection cross section is insensitive to the value of the coupling  2

Complex Singlet: LHC Discovery Barger, Langacker, McCaskey, R-M, Shaugnessy Traditional search: CMSInvisible search: ATLAS Single component case (x 0 = 0) EWPT

SM Higgs? Three scalars: h 1,2 (Higgs-like) D (dark matter) LHC: WBF “Invisible decay” search D D D D SM Branching Ratios ? He et al Barger, Langacker, McCaskey, RM, Shaugnessy EWPT WIMP-Nucleus Scattering Viable Dark Matter ? Gonderinger, Lim, R-M 2 nd light state  TH <  WMAP  Xenon Br(inv) > 0.6

Higgs Portal: Simple Scalar Extensions ExtensionEWPTDMDOF May be low-energy remnants of UV complete theory & illustrative of generic features Real singlet Complex Singlet Real Triplet    ?    

      ~ ( 1, 3, 0 ) Fileviez-Perez, Patel, Wang, R-M: PRD 79: (2009); [hep-ph] EWPT: a 1,2 = 0 & = 0 DM & EWPT: a 1 = 0 & = 0 //

Real Triplet       ~ ( 1, 3, 0 ) Fileviez-Perez, Patel, Wang, R-M: [hep-ph] EWPT: a 1,2 = 0 & = 0 DM & EWPT: a 1 = 0 & = 0 // Small:  -param

Real Triplet       ~ ( 1, 3, 0 ) Fileviez-Perez, Patel, Wang, R-M: [hep-ph] EWPT: a 1,2 = 0 & = 0 DM & EWPT: a 1 = 0 & = 0 // Small:  -param

HW Question 3 Consider the real triplet extension in which there is no H 0 -   mixing: explain why    cannot decay to Standard Model fermions, unlike the H 0

Real Triplet       ~ ( 1, 3, 0 ) Fileviez-Perez, Patel, Wang, R-M: [hep-ph] New feature: gauge interactions & direct detection Y = 2 ( Q - I 3 ) g  Z / 2 I Q sin 2  W Want Y = 0

Real Triplet       ~ ( 1, 3, 0 ) Fileviez-Perez, Patel, Wang, R-M: [hep-ph] New feature: gauge interactions & LHC production q q     W + q q     Z 0 EW cross sections w/ charged states + E T

LHC Phenomenology SM Branching Ratios ? Four scalars: h 1 (Higgs-like)   (dark matter)     (new states) SM “background” well below new CPV expectations New expts: 10 2 to 10 3 more sensitive CPV needed for BAU? D D D D Fileviez-Perez, Patel, R-M, Wang LEP: M  > 100 GeV ! BR(invis) = 0

Real Triplet : Charged BRs Charged: x 0 dependence Below WZ Threshold Above WZ Threshold Pure gauge x 0 supressed

Real Triplet : DM Search Basic signature: Charged track disappearing after ~ 5 cm SM Background: QCD jZ and jW w/ Z !  & W!l Trigger: Monojet (ISR) + large E T Cuts: large E T hard jet One 5cm track Cirelli et al: M  = 500 GeV:    CDM ~ 0.1

SM Higgs? SM “background” well below new CPV expectations New expts: 10 2 to 10 3 more sensitive CPV needed for BAU? SM Branching Ratios ? Four scalars: h 1 (Higgs-like)   (dark matter)     (new states) D D D D Fileviez-Perez, Patel, R-M, Wang   

Real Triplet : H 1 Decays Neutral SM-like Higgs: H + loops and BR ( H 1 !  ) X 0 =0: DM caseX 0 >0: EWPT case

SM Higgs? SM “background” well below new CPV expectations New expts: 10 2 to 10 3 more sensitive CPV needed for BAU? LHC: H !  D D D D   

Is it a Scalar ? Real singlet Complex Singlet Real Triplet ExtensionEWPTDM    ?     DOF

Is it a Scalar ? Real singlet Complex Singlet Real Triplet ExtensionEWPTDM    ?     DOF Mixed Higgs-like states and/or modified BRs: signal reduction  invisible search…

Is it a Scalar ? Real singlet Complex Singlet Real Triplet ExtensionEWPTDM    ?     DOF Could be fermionic triplet [e.g., Buckley, Randall, Shuve, JHEP 1105 (2011) 97]. How to distinguish?

Di-Jet Correlations J1J1 J2J2 V V p1p1 p2p2 Buckley, R-M JHEP 1109 (2011) 094 R-hadrons from gg fusion Scalars Fermions

New Scalars &  BSM Preserving EW Min“Funnel plot” V EFF  perturbativity m H top loops naïve stability scale  EW vacuum Gonderinger, Li, Patel, R-M SM stability & pert’vity SM unstable above ~ 8 TeV top loops sets m H

New Scalars &  BSM Preserving EW Min“Funnel plot” V EFF  perturbativity m H top loops naïve stability scale  EW vacuum top loops Gonderinger, Li, Patel, R-M SM stability & pert’vity SM + singlet: stable but non-pertur’tive DM-H coupling

Dark Matter Stability Preserving EW Min“Funnel plot” Gonderinger, Li, Patel, R-M V EFF  perturbativity m H ?  s Z 2 -breaking vacuum Z 2 -preserving EW vacuum No DM: Z 2 -breaking vac top loops naïve stability scale  EW vacuum m S 2 = b 2 + a 2 v 2

V. Long Range Dark Forces

Torsion Balances & Dark Forces New interactions in the dark sector ? Long-range, non-grav dark force Violation of weak equiv principle (WEP) Galactic tidal streams & CMB New hierarchy problem Non-sterile DM & terrestrial WEP tests Carroll, Mantry, RM, Stubbs Bovy & Farrar Kesden & Kamionkowski Eot-Wash Microscope

Summary There exist a number of interesting and viable “portals” for probing the dark sector The Higgs portal is particularly interesting now in light of the LHC discovery, and it raises many new questions Discovering scalar dark matter via the Higgs portal could make the idea of scalar fields in the early universe more plausible Simple scalar sector extensions that embody features of UV complete theories illustrate key features of the theory and phenomenology of scalar dark matter ! A rich and exciting period of experiment and theory lies ahead

Back Up Slides

Real Triplet : DM Search Basic signature: Charged track disappearing after ~ 5 cm SM Background: QCD jZ and jW w/ Z !  & W!l Trigger: Monojet (ISR) + large E T Cuts: large E T hard jet One 5cm track

Real Triplet : DM Search Basic signature: Charged track disappearing after ~ 5 cm SM Background: QCD jZ and jW w/ Z !  & W!l Trigger: Monojet (ISR) + large E T

LHC Phenomenology Signatures EWPO compatible m 2 > 2 m 1 m 1 > 2 m 2 LHC: reduced BR(h SM) Signal Reduction Factor ProductionDecay CMS 30 fb -1  SM-like Singlet-like SM-like SM-like w/ H 2 ->H 1 H 1 or Singlet-like ~ EWB Viable Light: all models Black: LEP allowed Scan: EWPT-viable model parameters LHC exotic final states: 4b-jets,  + 2 b-jets… EWPO comp w/ a 1 =0=b 3 LHC: reduced BR(h SM) Probing   : WBF H ! ZZ! 4 l H ! WW! 2j l Early LHC discovery possible Determine  as low as ~ 0.5

DM & Higgs Phenomenology Relic Density Direct Detection Vac stability He, Li, Li, Tandean, Tsai Gonderinger, Li, Patel, R-M He, Li, Li, Tandean, Tsai Barger, Langacker, McCaskey, R-M, Shaugnessy

LHC & Higgs Phenomenology Vac stab & perturbativityInvisible decays He, Li, Li, Tandean, Tsai Gonderinger, Li, Patel, R-M

LHC & Higgs Phenomenology Vac stab & pertubativityInvisible decays LHC discovery potential  (h!SS)=0 Invis search He, Li, Li, Tandean, Tsai Gonderinger, Li, Patel, R-M Barger, Langacker, McCaskey, R-M, Shaugnessy

Real Triplet : Charged BRs I Charged: x 0 dependence Pure gauge x 0 suppressed

Real Triplet : Heavy Neutral State Neutral: differences with SM Higgs & a 2 dependence Different ratio of WW and ZZ,  BRs

DM & Higgs Phenomenology Relic DensityVac stability He, Li, Li, Tandean, Tsai Gonderinger, Li, Patel, R-M