Dark Matter in theDark Matter in theLeft Right Twin Higgs ModelLeft Right Twin Higgs Model

Ethan DolleEthan Dolle

University of ArizonaUniversity of Arizona

Work done withWork done with

Shufang Su and Jessica GoodmanShufang Su and Jessica Goodman

OutlineOutline

• Left Right Twin Higgs ModelLeft Right Twin Higgs Model

• Relic Density AnalysisRelic Density Analysis

• Direct and Indirect DetectionDirect and Indirect Detection

• ConclusionConclusion

Left Right Twin Higgs ModelLeft Right Twin Higgs Model

•Chacko, Goh, and Harnik: Chacko, Goh, and Harnik: arXiv:hep-ph/0506256v1arXiv:hep-ph/0506256v1

•solution to Little Hierarchy Problem

•To avoid EW precision constraints, add a second Higgs Ĥ that couple to gauge boson only

Left Right Twin Higgs ModelLeft Right Twin Higgs Model

SU(2)SU(2)LL Higg doublet Higg doublet

SM Higgs doubletSM Higgs doublet

Couples only toCouples only to

gauge bosonsgauge bosons

DM candidateDM candidate

EWSBEWSB

Left Right Twin Higgs ModelLeft Right Twin Higgs Model

• Ĥ couples only to gauge bosonsĤ couples only to gauge bosons could be achieved by impose a discrete symmetry could be achieved by impose a discrete symmetry

• the lighter one of S, and A are stable, weakly the lighter one of S, and A are stable, weakly interactinginteracting

GoodGood

BadBad

⇒⇒Natural WIMP candidatesNatural WIMP candidates

Left Right Twin Higgs ModelLeft Right Twin Higgs Model

• h1 and h2 mass splittingh1 and h2 mass splitting

• Need to impose mass splitting between ANeed to impose mass splitting between A and S: Constraints from direct detection and S: Constraints from direct detection

Left Right Twin Higgs ModelLeft Right Twin Higgs Model

• Similar to Inert Higgs Doublet ModelSimilar to Inert Higgs Doublet Model

•Proposed by Barbieri, et al.•arXiv:hep-ph/0603188v2

•Dark matter analyzed by Honorez, et al.•arXiv:hep-ph/0612275

•Indirect detection analyzed by Gustafsson, et al.•arXiv:astro-ph/0703512

Model ComparisonModel Comparison

Inert Higgs Doublet Inert Higgs Doublet ModelModel

Left Right Twin Higgs ModelLeft Right Twin Higgs Model

MMhsm hsm ~ 500 GeV~ 500 GeV MMhsmhsm ~ 170 GeV ~ 170 GeV

New particlesNew particles New particlesNew particles

extra extra scalarsscalars extra scalarsextra scalars

Heavy gauge bosonsHeavy gauge bosons

Heavy top, heavy neutrinosHeavy top, heavy neutrinos

Relic Density AnalysisRelic Density Analysis

• WMAP: 0.093<ΩhWMAP: 0.093<Ωh22<0.128 at 2σ level<0.128 at 2σ level

•Must consider co-annihilations when mass splittings are small

•Used program micrOMEGAS_2.0•Solves Boltzmann equation exactly

•Need to solve Boltzmann equationNeed to solve Boltzmann equation

Relic Density AnalysisRelic Density Analysis

• Modest choice of parameters yields Modest choice of parameters yields

• High mass: MHigh mass: MSS ~ 500 GeV ~ 500 GeV

• Low mass: MLow mass: MSS<M<MWW ( in progress) ( in progress)

•Two regions:•Bulk•Pole•Due to heavy gauge bosons

Omg hOmg h22 vs M vs MSS

•Can change regions by changing:•f•mass splittings

Contour plot of Omg hContour plot of Omg h22

•MS in bulk region consistent

•Can change regions by changing mass splittings

Direct DetectionDirect Detection

• General idea: observe recoil of detector General idea: observe recoil of detector nuclei from dark matter collisionsnuclei from dark matter collisions

• Contributions from spin independent (SI) Contributions from spin independent (SI) and spin dependent (SD) cross sectionsand spin dependent (SD) cross sections

• Spin independent contribution dominatesSpin independent contribution dominates

Contributing ProcessesContributing Processes• First 2 are First 2 are

difficult to see difficult to see due to small due to small CW couplingsCW couplings• ~(gv)~(gv)22 instead instead

of usual ~(λv)of usual ~(λv)22

•Third process too big Third process too big (~10(~10-31-31 cm cm22))•Current CDMS limit: Current CDMS limit: ~10~10-43-43 cm cm22

•Impose A-S mass Impose A-S mass splitting to avoid splitting to avoid constraint constraint

• SI beats SD SI beats SD by 8 orders by 8 orders of magnitudeof magnitude

• THM THM predicts predicts values below values below future CDMS future CDMS limitslimits

• Difficult!Difficult!

Direct Direct Detection Detection

ExperimentsExperiments

Indirect DetectionIndirect Detection•General idea: dark matter annihilates into General idea: dark matter annihilates into photons, positrons, and neutrinosphotons, positrons, and neutrinos

•Looked at photonsLooked at photons

•Monochromatic photonsMonochromatic photons

•Hadronization and fragmentationHadronization and fragmentation

•Final state charged particle Final state charged particle radiationradiation

Indirect DetectionIndirect Detection

• Γ~(ρ)Γ~(ρ)22

• Increased events for areas of high densityIncreased events for areas of high density• Galactic HaloGalactic Halo• SunSun• EarthEarth

• High dependence on halo dark matter High dependence on halo dark matter density distributiondensity distribution

Monochromatic PhotonsMonochromatic Photons• Photon flux as a function of density:Photon flux as a function of density:

•Parameterize density with J:Parameterize density with J:

•Photon flux as a function of JΔΩ:Photon flux as a function of JΔΩ:

Monochromatic PhotonsMonochromatic Photons

• J gives the clumping of DM near galactic J gives the clumping of DM near galactic centercenter• Highly model dependentHighly model dependent

• 101033 for NFW profile for NFW profile• 101055 for Moore et al profile for Moore et al profile

• ΔΩ indicates field of view of telescopeΔΩ indicates field of view of telescope• 1010-3 -3 sr for ground based ACTs (typical)sr for ground based ACTs (typical)

• JΔΩ~1-100JΔΩ~1-100• Flux scales linearlyFlux scales linearly

Monochromatic PhotonsMonochromatic Photons

•Contributing processesContributing processes•Through loop processes onlyThrough loop processes only

•Difficult to observe due to Difficult to observe due to small couplingssmall couplings•Same problem as with direct Same problem as with direct detection!detection!

Hadronization and FragmentationHadronization and Fragmentation•Number as a function of Number as a function of EEγγ

•Spectra depends only on Spectra depends only on W/Z initial energiesW/Z initial energies

• Contributing processesContributing processes

Hadronization and FragmentationHadronization and Fragmentation•THM predictions THM predictions for 2 regionsfor 2 regions•Detector limits:Detector limits:•GLASTGLAST•ACTsACTs

•Difficult, unless Difficult, unless J is largeJ is large•DM strongly DM strongly clumped at clumped at galactic centergalactic center

GLAST

ACT

BULK

POLE

J ΔΩ = 1J ΔΩ = 1

Final state radiationFinal state radiation

Contributing ProcessesContributing Processes

Final State RadiationFinal State Radiation

•Predictions for Predictions for THMTHM•2 processes2 processes•Unique knee Unique knee signaturesignature•2 orders of 2 orders of magnitude magnitude below detector below detector limitslimits•Difficult!Difficult!

J ΔΩ = 1J ΔΩ = 1

BULK

POLE

ConclusionConclusion• Left Right Twin Higgs Model provides a Left Right Twin Higgs Model provides a

natural dark matter candidatenatural dark matter candidate

• Can explain 100% of dark matter observed Can explain 100% of dark matter observed by WMAPby WMAP

• Direct detection difficultDirect detection difficult

• Indirect detection: hadronization possible, Indirect detection: hadronization possible, other 2 are difficultother 2 are difficult

• Thank you!Thank you!