Neutralino Dark Matter from GUT-Less SUSY

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SUSYSUSYSUSYSUSY DarkDarkDarkDark MatterMatterMatterMatter (updates(updates(updates(updates andandandand asides)asides)asides)asides)

Pearl Sandick the University of Texas at Austin DarkDarkDarkDark MatterMatterMatterMatter Kowalski et al. (2008) WMAP

● ΩDM= 0.233 ± 0.0013 Komatsu et al. (2009) ● It's non-baryonic (BBN+CMB, structure formation). ● It's stable or very long-lived. ● It's not charged (heavy isotope abundances). ● It's largely non-relativistic (cold).

85% of the matter density of the universe is unexplained by the Standard Model.

Pearl Sandick, UT Austin PlanPlanPlanPlan

• SUSY Dark Matter (WIMPs and WIMPier) • How to find it • Who's looking

Pearl Sandick, UT Austin SUSYSUSYSUSYSUSY DarkDarkDarkDark MatterMatterMatterMatter

• The LSP may be an excellent dark matter candidate 2 2 • The lightest one may be stable (WIMP?) with Ωχh ≈ ΩDMh The lightest SUSY particle (LSP) is stable if R-parity is conserved.

+1 for SM particles R = (-1)3 B + L += 2 S -1 for sparticles

Why conserve R-parity? Ad hoc? •Stability of proton •SO(10) GUTs •Neutron-antineutron oscillations •B and L numbers become •Neutrino mass accidental symmetries of SUSY

Pearl Sandick, UT Austin WhyWhyWhyWhy SUSY?SUSY?SUSY?SUSY?

● Aesthetically “neat” extension ● Stabilizes the Higgs vev (Hierarchy Problem) Just right! ● Gauge coupling unification ● Predicts a light Higgs boson

∆ 2 ∝ Λ mH log( UV ) < < 2 ( mH )

Pearl Sandick, UT Austin MSSMMSSMMSSMMSSM

Also quarks and squarks axion: a, spin 0 saxion: s, spin 0 leptons and ~ axino: a, spin ½ sleptons graviton: G, spin 2 ~ W boson and wino gravitino: G, spin 3/2 gluon and gluino B boson and bino

Higgs bosons and higgsinos

Pearl Sandick, UT Austin SuperWIMPsSuperWIMPsSuperWIMPsSuperWIMPs (E-WIMPs)(E-WIMPs)(E-WIMPs)(E-WIMPs)

• Interaction scale with ordinary matter suppressed by large mass scale:

➔ 19 For gravitino, mP ≈ 10 GeV (gravitational interactions)

➔ 11 For axino, fa ≈ 10 GeV

2 σ ≈ (mW/ fa) σweak

-18 ≈ 10 σweak ≈ 10-20 pb

Choi & Roszkowski (2005) Pearl Sandick, UT Austin AxinosAxinosAxinosAxinos

• Axion is a solution to the strong CP problem, i.e. Why does QCD conserve CP when CP violating operators are allowed? – Peccei-Quinn Mechanism: Promote CP-violating operator to a field by requiring new global (P-Q) symmetry – P-Q symmetry is spontaneously broken → Axion is Goldstone Boson (“pseudo” due to small mass from QCD vacuum effects) – SUSY: axion is in a chiral multiplet with axion + saxion, axino:

• Axion gets its mass from QCD effects: • SUSY breaking splits saxion/axino masses from tiny axion mass

– ms~ mSUSY (not LSP)

– m~a unconstrained (could be LSP and DM)

Pearl Sandick, UT Austin AxinoAxinoAxinoAxino DarkDarkDarkDark MatterMatterMatterMatter

• If the axino is the LSP, expect see Baer et al. (2010) and references therein

non-thermally produced axinos from neutralino NLSP decay axions from vacuum mis-algnment mechanism

thermally produced axinos from radiation off MSSM scattering processes

• TP axinos are CDM for

Pearl Sandick, UT Austin GravitinoGravitinoGravitinoGravitino DarkDarkDarkDark MatterMatterMatterMatter

• Like axino, both thermal and non-thermal production mechanisms

– NTP: • Late decays of NLSP can lead to entropy overproduction and hot dark

matter, so mNLSP > 500 GeV

2 • ΩGh ~ 0.1 for 1 GeV < mG < 700 GeV (Steffen, 2006)

– TP:

• TR << Tf to avoid overproduction of gravitinos (“Gravitino Problem”)

2 • For natural ranges of gluino and gravitino masses, one can have TP ΩGh ~ 9-10 0.1 at TR as high as 10 GeV. • NLSP decays produce energetic SM particles, could spoil BBN light element abundances

Pearl Sandick, UT Austin GravitinoGravitinoGravitinoGravitino MassMassMassMass

• Gravitino mass depends on how SUSY breaking is communicated to the observable sector: – Gravity (modulus) mediated SUSY: maybe LSP • m3 / 2 ≈ 100 GeV − few TeV – Anomaly mediated SUSY: not LSP • m3 / 2 ≈ 10 TeV – 100 TeV – Gauge mediated SUSY: probably LSP • m3 / 2 ≈ 10 eV – 1 GeV – Gaugino mediated SUSY: maybe LSP

• m3 / 2 ≈ 10 GeV – TeV WIMPWIMPWIMPWIMP DarkDarkDarkDark MatterMatterMatterMatter

Expansion and annihilation 1 compete to determine the 2 number density:

Stable matter with GeV-TeV mass and weak-scale interaction strength yield Ωh2 ~ 0.1 Jungman, Kamionkowski and Griest, PR 1996

Pearl Sandick, UT Austin SneutrinosSneutrinosSneutrinosSneutrinos

• L-handed neutrinos have L-handed sneutrino superpartners in the MSSM – Large coupling to Z boson leads to low relic abundance and larger-than-observed scattering rates with nuclei. Falk, Olive & Srednicki (1994) – Low mass window closed by limits from invisible Z decay at LEP. LEPEWWG (2003) • R-handed neutrinos can be added to the SM to explain the origin of neutrino masses, so expect R-handed sneutrino partners. – L-R mixed sneutrinos have reduced coupling to Z, but a significant L-R mixing is only possible in very particular SUSY-breaking scenarios. – Pure R-handed sneutrinos could be CDM, but can't be thermal relics because their coupling to ordinary matter is very small. These ARE viable DM candidates in SUSY models with extended gauge or Higgs sectors (and therefore additional matter interactions). Arina & Fornengo (2007), Asaka, Ishiwata & Moroi (2007), Cerdeno & Seto (2009), etc.

Pearl Sandick, UT Austin SneutrinosSneutrinosSneutrinosSneutrinos

Allahverdi et al. (2007, 2009) • Example: MSSM + gauged U(1)B-L

– DM could be R-sneutrino if U(1)B-L is broken at ~TeV scale. • Example: MSSM + singlet superfield S for μ problem + singlet superfield N for R-(s)neutrino states Cerdeno & Seto (2009) – DM is pure R-sneutrino with couplings to MSSM fields, so it has the properties of a thermally-produced WIMP. • Example: MSSM + 6 complex sneutrino fields (12 mixed L/R sneutrino mass eigenstates) March-Russell, McCabe & McCullough (2009) – DM could be lightest sneutrino, or combination of long-lived sneutrinos Bottom line: Sneutrino DM must be substantially R-handed to suppress coupling to Z, so generally arises in extended versions of the MSSM. Properties of sneutrino depend on the MSSM extension – many possibilities. Pearl Sandick, UT Austin NeutralinosNeutralinosNeutralinosNeutralinos

• The LSP is a neutralino in much of parameter space of even most-constrained SUSY models. 2 2 • The lightest one may be a stable WIMP with Ωχh ≈ ΩDMh

Properties of neutralino LSP depend on its composition.

Pearl Sandick, UT Austin DarkDarkDarkDark MatterMatterMatterMatter DetectionDetectionDetectionDetection

• Colliders – Produce Dark Matter directly (missing energy signature) – Observe decays of NLSPs • Direct Detection – Observe WIMPs through interactions with matter in terrestrial detectors (axions?) • Indirect Detection – Observe products of WIMP annihilation/decay in terrestrial or space-based detectors

Pearl Sandick, UT Austin PlanPlanPlanPlan FromFromFromFrom HereHereHereHere

• Direct Detection, current status, what it means for SUSY, and tensions • Indirect Detection, current status, what it means for SUSY, and other possibilities • LHC/ILC – dark matter connection DirectDirectDirectDirect DetectionDetectionDetectionDetection CaseCaseCaseCase StudyStudyStudyStudy

• CMSSM: GUT-scale universality – Scalar masses – Gaugino masses – Trilinear couplings – tan(beta) – sign(mu)

spin dependent (axial vector) spin independent (scalar) • Fraction of nucleus participates • Whole nucleus participates • Important for capture & annihilation • Best prospects for direct detection rates in the sun CMSSMCMSSMCMSSMCMSSM

Ellis, Olive, Sandick (2009)

Focus Point

Coannihilation Strip

Pearl Sandick, UT Austin CMSSMCMSSMCMSSMCMSSM

Ellis, Olive, Sandick (2009)

XENON10 CDMS II

SuperCDMS XENON100

Pearl Sandick, UT Austin DeparturesDeparturesDeparturesDepartures fromfromfromfrom CMSSMCMSSMCMSSMCMSSM

• More general patterns of FCNC suppression suggests universality of SUSY breaking: matter fields that share quantum numbers – NU scalar masses m 0 SUSY GUTs: varying degrees of • NU Higgs masses? universality •SO(10): mH, m0, M1/2 – NU gaugino masses M1/2 •SU(5): some masses equal

NU trilinear couplings A mSUGRA: m (also for Higgses), M – 0 0 1/2

• Extended particle content mirage mediation: universality below the – NMSSM GUT scale (GUT-less SUSY) extra singlet – nMSSM some string scenarios for SUSY breaking: superfield maybe no universality at any scale! – UMSSM – etc. Pearl Sandick, UT Austin NUHMNUHMNUHMNUHM

Ellis, Olive, Sandick (2009) NUHM1 CMSSM

Pearl Sandick, UT Austin DirectDirectDirectDirect SearchesSearchesSearchesSearches

• Searches • Signals... (+ example of SUSY model- building to accommodate them) • Current limits, projected sensitivities StrategiesStrategiesStrategiesStrategies &&&& SearchesSearchesSearchesSearches

● One-channel – Ionization: GENIUS, IGEX, HDMS, TEXONO, CoGeNT – Scintillation: DAMA, NAID, DEAP, CLEAN, XMASS, KIMS – Phonons: CUORE, CRESST-I – Bubble Chambers: PICASSO, COUPP ● Two-channel (better BG discrimination) – I+P: EDELWEISS, EUREKA, CDMS, SuperCDMS – I+S: ArDM, ZEPLIN, WARP, XENON, LUX – S+P: CRESST-II SDSDSDSD StatusStatusStatusStatus

χ-n χ-p SISISISI StatusStatusStatusStatus (~1(~1(~1(~1 yearyearyearyear ago)ago)ago)ago)

CoGeNT Collaboration (2010)

CDMS-II (2 events) DAMA CoGeNT exclusion CoGeNT signal CMSSM (shaded) CoGeNTCoGeNTCoGeNTCoGeNT SISISISI StatusStatusStatusStatus (~1(~1(~1(~1 yearyearyearyear ago)ago)ago)ago)

CoGeNT Collaboration (2010)

CDMS-II (2 events) DAMA CoGeNT exclusion CoGeNT signal CMSSM (shaded) IsIsIsIs itititit MSSM?MSSM?MSSM?MSSM?

• No. Feldman et al. (2010)

• NMSSM? Also no. (though maybe with a generic extra chiral singlet superfield) PossiblePossiblePossiblePossible ResolutionResolutionResolutionResolution

CDMS II (2010)

DAMA/LIBRA CoGeNT

CDMS II 2 keV (solid) CDMS II 10 keV (dot-dashed) XENON100 XENON10 CRESST LookingLookingLookingLooking ForwardForwardForwardForward

Projected sensitivity to MOST SUSY WIMP dark matter models.

If it's not a WIMP, wrong tree...

If these techniques don't find it...? -> Need directional detection: DMTPC (irreducible neutrino background) IndirectIndirectIndirectIndirect SearchesSearchesSearchesSearches

• What to look, where to look for it • Recent excitement (+ SUSY model- building response) IndirectIndirectIndirectIndirect SearchesSearchesSearchesSearches

Galactic Center Milky Way Halo Satellites

Annihilation in our Sun/Earth (capture)

Spectral Lines (small BR)

Extra-Galactic (galactic background) FinalFinalFinalFinal StateStateStateState

Bertin et al. 2002 IndirectIndirectIndirectIndirect SearchesSearchesSearchesSearches

• photons – γ-Rays: Fermi, VERITAS, MAGIC, HESS... – Microwave (synchrotron): WMAP, Planck • neutrinos – Super-Kamiokande, IceCube, KM3NeT • electrons/positrons, protons/antiprotons – Fermi, PAMELA, AMS... positronspositronspositronspositrons

PAMELA positron fraction: Fermi electron + positron flux:

Adriani et al. 2008 Ackermann et al. 2011 SUSYSUSYSUSYSUSY model-buildingmodel-buildingmodel-buildingmodel-building

• non-thermal wino dark matter (Kane et al.) – no direct detection signals, due to ~100% wino content – requires substantial tuning of the propagation model • nearby [neutralino] dark matter clumps (Hooper et al.) – maybe signals indicate substructure? • TeV-scale boosted leptophilic dark matter in SUSY extensions – e.g. gauged U(1)B-L: lightest neutralino in the B-L sector, or RH sneutrino (Allahverdi, Dutta et al.) • B-L neutralinos -> 2 B-L Higgses (~10 GeV, decay to fermions) – Sommerfeld enhancement, SI scattering (>~ 10-10 pb), no SD, possible Z' @ LHC, gamma-rays in FGST... • RH sneutrino, same dominant annihilation mode – Sommerfeld, SI scattering (10-9 – 10-11 pb), no SD, but leptonic ann. -> neutrinos from the Sun detectable, Z' @ LHC, gamma-rays AMS-02AMS-02AMS-02AMS-02

Launch ~19 April, 2011

Proton rejection of 10-6 !!

(for Ee+ < 300 GeV) PAMELA claims 10-5, though some are skeptical... NeutrinosNeutrinosNeutrinosNeutrinos

Sandick et al. (2010)

IceCube discovery reach (10 yrs.)

Mandal et al. (2010) NeutrinosNeutrinosNeutrinosNeutrinos fromfromfromfrom thethethethe SunSunSunSun

Ellis et al. (2010) Gamma-RaysGamma-RaysGamma-RaysGamma-Rays

Abdo et al. (2010) Gamma-RaysGamma-RaysGamma-RaysGamma-Rays

Fermi-LAT Collaboration (2010)

Baltz et al. JCAP 0807, 2008 CollidersCollidersCollidersColliders

• Status from LHC (haven't found SUSY or Dark Matter) • What the LHC can find: new weak-scale physics • Follow-up measurements with a linear collider... • Need DD or LC to prove dark matter SuperWIMPSuperWIMPSuperWIMPSuperWIMP DarkDarkDarkDark MatterMatterMatterMatter

• Unfortunately, no [traditional] direct or indirect WIMP detection signals are expected for stable axino/gravitino dark matter. • If R-parity is broken, decaying axinos/gravitinos may be responsible for the PAMELA positron excess. – Depending on R-parity breaking model, radiative or leptonic decay channels may be preferred. • Collider signatures are possible, but depend on NLSP: – Charged NLSP would be easy to see, but would need to carefully study its decays to determine what the LSP is. Decays would likely happen outside the detector (need to trap sleptons) – Neutral NLSP would be harder to see, and could itself be dark matter. Mass and couplings compatible? see, for example, Covi et al. (2001), Covi & Kim (2009)

Pearl Sandick, UT Austin GravitinoGravitinoGravitinoGravitino vs.vs.vs.vs. AxinoAxinoAxinoAxino

• Can we tell them apart? • Maybe! If long-lived staus are accumulated and observed, we might be able to determine if CDM is axino or gravitino based on stau decay event distributions.

Brandenburg et al. (2005)

Pearl Sandick, UT Austin SummarySummarySummarySummary

• Direct Detection: Hints, but probably not dark matter – Increase in sensitivity is promising (news before 2012?) • Indirect Detection: Hints, but probably not dark matter – AMS will help unravel mystery – Coincident signals would be great; need to show (at least) that dark matter is the BEST explanation, not just a possible explanation • Colliders: [discuss] EXTRAEXTRAEXTRAEXTRA SLIDESSLIDESSLIDESSLIDES SUSYSUSYSUSYSUSY DMDMDMDM CandidatesCandidatesCandidatesCandidates

• A plethora of DM candidates: – neutralinos (our favorite WIMPs) • H. Goldberg, Phys. Rev. Lett. 50, 1419 (1983); J. Ellis, J. Hagelin, D.V. Nanopoulos, K. Olive, and M. Srednicki, Nucl. Phys. B 238, 453 (1984), etc. – sneutrinos (also WIMPs) • T. Falk, K. A. Olive and M. Srednicki, Phys. Lett. B 339 (1994) 238; T. Asaka, K. Ishiwata, and T. Moroi, Phys. Rev. D 73, 051301 (2006); 75, 065001 (2007); F. Deppisch and A. Pilaftsis, J. High Energy Phys. 10 (2008) 080; J. McDonald, J. Cosmol. Astropart. Phys. 01 (2007) 001; H. S. Lee, K. T. Matchev, and S. Nasri, Phys. Rev. D 76, 041302 (2007); D. G. Cerdeno, C. Munoz, and O. Seto, Phys. Rev. D 79, 023510 (2009); D. G. Cerdeno and O. Seto, J. Cosmol. Astropart. Phys. 08 (2009) 032; etc. – gravitinos (SuperWIMPs) • J.L. Feng, A. Rajaraman and F. Takayama, Phys. Rev. Lett. 91, 011302 (2003) [hep-ph/0302215], Phys. Rev. D 68, 063504 (2003) [hep-ph/0306024]; J.R. Ellis, K.A. Olive, Y. Santoso and V.C. Spanos, Phys. Lett. B 588, 7 (2004) [hep-ph/0312262]; J.L. Feng, S.f. Su and F. Takayama, Phys. Rev. D 70, 063514 (2004) [hep-ph/0404198]; etc. – axinos (SuperWIMPs) • T. Goto and M. Yamaguchi, Phys. Lett. B 276, 103 (1992); L. Covi, H.B. Kim, J.E. Kim and L. Roszkowski, JHEP 0105, 033 (2001) [hep-ph/0101009]; L. Covi, L. Roszkowski, R. Ruiz de Austri and M. Small, JHEP 0406, 003 (2004) [hep-ph/0402240]; etc.

Pearl Sandick, UT Austin ““““WIMPWIMPWIMPWIMP Miracle”Miracle”Miracle”Miracle”

1. New (heavy) particle χ 1 in thermal equilibrium: 2 χ χ ⇄ f f 2. Universe expands 3 and cools: χ χ ⇄ f f 3. χ's “freeze out” χ χ ⇄ f f Jungman, Kamionkowski and Griest, PR 1996

Pearl Sandick, UT Austin WhyWhyWhyWhy SUSY?SUSY?SUSY?SUSY?

● Aesthetically “neat” extension

R. Haag, J. T. Lopuszanski and M. Sohnius Nucl. Phys. B 88 (1975) 257

Extended the Poincare algebra: Q |boson> = |fermion> and Q |fermion> = |boson> Find a consistent theory with interplay of Poincaré and internal symmetries.

Supersymmetry is the only nontrivial extension of the Pioncaré algebra in a consistent 4-d QFT.

Pearl Sandick, UT Austin WhyWhyWhyWhy SUSY?SUSY?SUSY?SUSY?

● Aesthetically “neat” extension ● Stabilizes the Higgs vev (Hierarchy Problem)

2  2  4 2 V = mH | | + λ| | λ SM: ∆ 2 = − f Λ 2 + From W and Z masses, know m< H>=174 GeV,2 UV ... 2 2 8π so expect |m | ~ (100 GeV) h

∆ 2 ∝ Λ < < 2 SUSY: mH log( UV ) mH

SUSY maintains hierarchy of mass scales.

Pearl Sandick, UT Austin WhyWhyWhyWhy SUSY?SUSY?SUSY?SUSY?

● Aesthetically “neat” extension ● Stabilizes the Higgs vev (Hierarchy Problem) ● Gauge coupling unification

Near miss! Just right!

Running (b’s) depends only on particle content of the model.

Pearl Sandick, UT Austin WhyWhyWhyWhy SUSY?SUSY?SUSY?SUSY?

● Aesthetically “neat” extension ● Stabilizes the Higgs vev (Hierarchy Problem) ● Gauge coupling unification ● Predicts a light Higgs boson

MSSM: 105 GeV <~ mh ~< 135 GeV

LEP: 114.4 GeV < mh < 157 GeV LEP Collaborations and Electroweak Working Group, August 2009

Pearl Sandick, UT Austin MSSMMSSMMSSMMSSM

MSSM:

Minimal Supersymmetric Standard Model

Has the minimal particle content possible in a SUSY theory.

Pearl Sandick, UT Austin SUSYSUSYSUSYSUSY BreakingBreakingBreakingBreaking (pheno.)(pheno.)(pheno.)(pheno.)

Don’t observe boson-fermion degeneracy, so SUSY must be broken (How?) Most general case (MSSM) has > 100 new parameters! OR make some assumptions about SUSY breaking at a high scale, and evolve mass parameters down to low scale for observables Explicitly add [soft] SUSY-breaking terms to the theory: Masses for all gauginos and scalars Couplings for scalar-scalar and scalar-scalar-scalar interactions

Example: CMSSM (similar to mSUGRA)

Assume universality of soft SUSY-breaking parameters at MGUT

Free Parameters: m0, m1/2, A0, tan(β), sign(μ)

Pearl Sandick, UT Austin ConstraintsConstraintsConstraintsConstraints

Apply constraints from colliders and cosmology:

mh > 114 GeV m > 104 GeV LEP χ± BR(b → s γ) HFAG 0.09 ≲ Ω h2 ≲ 0.12 + -- χ BR(Bs → µ µ ) CDF

(gµ - 2)/2 g-2 collab.

Pearl Sandick, UT Austin CMSSMCMSSMCMSSMCMSSM

LEP Higgs mass

Relaxed LEP Higgs LEP chargino mass µ2 < 0 (no EWSB)

gµ-2 suggested region stau LSP

Ellis, Olive, Sandick (2006)

Pearl Sandick, UT Austin CMSSMCMSSMCMSSMCMSSM

b→sγ

B→μ+μ--

Ellis, Olive, Sandick (2006)

Pearl Sandick, UT Austin CMSSMCMSSMCMSSMCMSSM

Focus Point LEP Higgs mass

Relaxed LEP Higgs LEP chargino mass µ2 < 0 (no EWSB)

gµ-2 suggested region stau LSP Coannihilation Strip

Ellis, Olive, Sandick (2006)

Pearl Sandick, UT Austin AxinoAxinoAxinoAxino DarkDarkDarkDark MatterMatterMatterMatter

Covi et al. (2004); Choi and Roszkowski (2005) Pearl Sandick, UT Austin GravitinoGravitinoGravitinoGravitino DarkDarkDarkDark MatterMatterMatterMatter

• Neutrino signals? Only if gravitino is unstable... (RPV) – NLSP decays to SM particles quickly – Gravitinos TP at reheating – Long-lived, ~150 GeV gravitinos decay, contributing to the CR positron excess and the diffuse gamma-ray flux Covi et al. (2009)

Pearl Sandick, UT Austin CMSSMCMSSMCMSSMCMSSM

Rapid annihilation funnel ≈ 2mχ mA b→sγ

B→μ+μ--

Ellis, Olive, Sandick (2006)

Pearl Sandick, UT Austin DeparturesDeparturesDeparturesDepartures fromfromfromfrom CMSSMCMSSMCMSSMCMSSM

NU trilinear couplings A mSUGRA: m (also for Higgses), M – 0 0 1/2

CMSSM – Higgs masses determined by NUHM1 – One extra free parameter: NUHM2 – No constraint at GUT scale

CMSSM GUT-scale inputs: Use electroweak vacuum conditions:

Pearl Sandick, UT Austin IndirectIndirectIndirectIndirect DetectionDetectionDetectionDetection

s-wave zero relative velocity

• Bino: heavy fermions [down-type favored for large-ish tan(β)], WW • Wino: gauge bosons • Higgsino: gauge bosons

Example: Coannihilation Strip (mostly bino, 321 GeV) ~39% taus, ~27% WW, ~17% bb, ~15% tt

Example: Focus Point (bino-Higgsino mix, 140 GeV) ~94% WW, ~5% ZZ, ~1% hZ

Pearl Sandick, UT Austin ClosingClosingClosingClosing RemarksRemarksRemarksRemarks

• The identification of dark matter is a very interesting problem. • Supersymmetry is an attractive theory in which there are several possible dark matter candidates. – SuperWIMPs: Axino and Gravitino – WIMPs: Sneutrino and Neutralino • Dark matter phenomenology depends on many assumptions about SUSY breaking, but some general conclusions can be drawn (especially for MSSM neutralino dark matter). • We hope for agreement among many experiments and techniques (direct detection, indirect detection, and collider experiments) to give us a consistent picture of dark matter and its properties.

Pearl Sandick, UT Austin