Several models of New Physics, independently motivated, also offer viable candidates for weakly-interacting, neutral, heavy DM particle;

Supersymmetry with conserved R-parity:Lightest supersymmetric particle (LSP) stable can be DM candidate;Main candidate is lightest neutralino 0

1 whose relic density dependson mass and interaction with other particles (annihilation cross section)

Universal Extra dimensions with conserved KK-parity

Warped Extra dimensions with conserved Z1 parity…

Dark Matter may represent first direct signal of that New Physics at TeV scale which is a main focus of Tevatron, LHC and ILC physicsprogram;

Cosmologically interesting regions in cMSSM parameter space:

Bulk RegionCo-Annihilation Region

A0 Funnel RegionFocus Point Region

SUSY model analysis simplified within cMSSM: dimensionality of parameter space reduced by one (m1/2 m0): four regions emerge:

WIMP Dark Matter in cMSSM

Constrained MSSM useful template to define benchmarks, signatures;assessment of physics reach must be performed on full MSSM.

Observing DM-motivated NP at Tevatron

Low M3 Models at Tevatron

Scenarios with low SU(3) gaugino mass parameter, compatible with DM constraints have light gluinos, decaying radiatively g, and evade LEP-2 chargino lower limit, making them interesting for detection at Tevatron.

Baer et al., hep-ph/0610154

Tevatron reach in >2 Jets, ll + ETmissing

The Role of the Top Quark Mass

By end of Run-2 CDF+D0 should attain 1.5 GeV accuracy on Mtop

Mtop and relation between mtop(mtop) and pole mass drive precise location of

DM-compliant regions on (c)MSSM plane

Mstop1 in FP region

vs. Mtop

hep-ph0608322

Rare Bs decay at Tevatron

300 pb-1

CDF Preliminary (780 pb-1)BR(Bs ) < 1.0 x 10-7

Bds, Bs decays constrains low m0,m1/2 region of parameters: Bs most important in large tan scenarios:

hep-ph/0507283Ellis, Olive

hep-ph06031800611065

Dark Matter Direct Searches and Tevatron

Experiments at Tevatron currently probing high energy frontiersearching for SUSY Higgs signals;

LSP-nucleus scattering SI through t-channel A0 exchange correlatesDM direct searches to Collider searches for SUSY Higgs bosons;

CDF D0

Exclusion regions for discovery of

at Tevatron (2 x 4 fb-1)

Carena, Hooper, Skands, hep-ph/0603180

Negative CDMS results reduce likelihood of heavy SUSY Higgsdiscovery at Tevatron, while CDMS signal would make Tevatron discovery likely.

Dark Matter Direct Searches and Tevatron

Constraining DM density at LHC

LHC discovery reach independentof details of the model: ET

missing+jets and/or isolated leptons sufficientto ensure detection;

Consistency with DM requires asignificant number of measurements;

Perform tests first within context of specific model (cMSSM) and then reconstruct full decay chain enabling model-independent mass measurements;

Constraining DM density in Higgs Sector

Allanach et al.,hep-ph/0507283

Constraining DM density in Higgs Sector

D0 D0

Constraining DM density in Higgs Sector

ILC

0.5

TeV

ILC

1.0

TeV

A0 Funnel Region

Studying DM at Colliders beyond LHC

ILC to provide point-like particlecollisions from 0.3 TeV up to ~ 1 TeVwith tunable centre-of-mass energies,particle species and polarization states;

In a farther future, CLIC multi-TeV e+e- collider may further push energy frontier up to 3 – 5 TeV.

ILC-LHC Complementarity

ILC precision and versatility crucial in extending discoveries and fully testing nature of physics at the new frontier first explored by the LHC:

SUSY offers interesting template for complementarity in new particles to be discovered at LHC and ILC, but also for higher sensitivity to Cosmology-motivated scenarios at edges of phase space;

ILC offers unique probe in measuring quantum numbers and coupling and thus unravel relation of new signals to Supersymmetry, Extra Dimensions and other scenarios

Bulk Region

LCC1 Benchmark

Bulk Region at LHC

Availability of decay chains with multi-leptons, lepton+jets topologiesallows to determine masses from kinematical endpoints (but significantcorrelations from sensitivity to mass differences):

ATLASFull Simulation

Determine sparticle masses from kin.edges, neutralino mixing matrix frommass differences, tan from Higgs Sector and bound A mass; Specific point strongly constrained by measurements offer good accuracy in full MSSM:

Bulk Region at LHC

MSSMScan

LHC SPS1a’

(Model independent) =0.1 (stat)+/-0.1 (tan )+/-0.04 (m(2))

Nojiri, Polesello, Tovey, JHEP 0603 (2006)

300 fb-1

Due to endpoint constraints, mass differences better determined than absolute masses and estimated accuracy on endpoints crucial;

Bulk Region at ILC

Emin Emax

At ILC collisions of e+e- with well-defined, tunable energy makes possible mass and mass difference determinations by energy endpointsin 2-body decays and threshold scans

A Comparison of DM density accuracy at LHC and ILC in Bulk Region

WMAP

Co-Annihilation Region

LCC3 Benchmark

Dutta et al.,PLB 639 (2006)

Co-Annihilation Region at LHC

M = 10.6 GeV

Recent analysis showed feasibility ofa detailed study of co-annihilation region at LHC: Use di-tau Invariant Mass as M estimatorOS-LS to remove bkgs.

Dutta et al.,PLB 618 (2005)

Co-Annihilation Region at ILC

Determine M(1) - M(10) from

distribution of M(j1j2Emissing)

At 0.5 TeV production of 11 and resulting in Emissing final state;

Very Fwd Detector coverage controls minimumreachableM:

Jet h Fake Rate

Fake rate from CDF data: from 1.1% (20 GeV) to 0.2% (100 GeV)

ATLASAlgorithmic improvements expected at ATLAS and CMS,Mistag rate can be measured to 5-10% accuracy with 10 fb-1

Focus Point Region

At large m0, LSP has significant Higgsinocomponent and gets large coupling to WW and ZZ;

FP region can extend to very large m0 driving sfermion masses at, and beyond, the LHC reach;

Gauginos remain reasonably light andmostly accessible at ILC;

Baer et al.

Mixed Higgsino-gaugino nature of heavier neutralinos gives Z0 and h0

bosons in decay chains, with Z0 peak in ll invariant mass.

Focus Point Region

LCC2 Benchmark

Carena, Freytas, hep-ph/0608255

Stop co-Annihilation in Baryogenesis motivated Scenarios

Light scalar top, nearly degeneratewith neutralino, provides efficientco-annihilation and evades Tevatron searches due to small ET.

Baryogenesis constraints pushtowards heavy scalar and introduces CP-violating phase in .

LH

C

ILC

Scenario shares several features characteristic of FP region but requires analysis of real Z0 and light stops.

Models with real Z0 bosons

Production of real Z0 bosons in the decay of heavier neutralinos (i.e. 0

3 01 Z0) serves

as useful signature a LHC through Z0l+l-;

At ILC, measurement of E(Z0) endpoints can be used to determine M(0

3) – M(01)

which fixes the value of ;

CMS

ILC

A0 Funnel Region

LCC4 Benchmark

A0 Funnel Region at ILC

Determine MA fromreconstruction in 4-b jet events at 1 TeV;

Apply 4C constraints and determine MA and A from 5-par fit to Mjj spectrum using signal + quadratic background term:

Determine LSP and stau1 masses at 0.5 TeV;

Collider Experiments on Dark Matter

Baltz, M.B., Peskin, Wiszanski, PRD74 (2006)

Dark Matter Density

0.19

0.18

ILC Accuracy within MSSM on cMSSM plane

Collider Experiments on Dark Matter

Baltz, M.B., Peskin, Wiszanski, PRD74 (2006)

Spin-Independent Neutralino Proton Cross Section

Complementarity with Direct DM Searches

Expect significant complementaritybetween collider data and direct detection:

In several scenarios, direct detection may provide constraints on MA beyond LHC/ILC reach or in FP scenarios even extend sensitivity to regions of parameter space with reduced LHC sensitivity;

In co-annihilation region, direct detection cross section can fix nature of LSP (gaugino-Higgsino mixing).

Collider Experiments on Dark Matter

Baltz, M.B., Peskin, Wiszanski, PRD74 (2006)

Effective Local WIMP Flux at Earth

SuperWIMP Dark Matter at Colliders

Possible scenario with WIMP decaying into superWIMP, such as: long lifetime (~1 yr) WIMP produced at colliderscould be detected as heavy charges particle in dedicated setup, its lifetime and mass differenceto the Gravitino measured;

J. Feng et al. hep.ph/0410178

non-SUSY WIMP Dark MatterSeveral scenarios of New Physics may include a symmetry protecting a cold DM candidate: Warped Extra Dimensions, Radions, Universal Extra Dimensions,...

UED interesting case study, with a phenomenology close to SUSY and particle at a mass scale below 1 TeV to comply with WMAP constraint.

Servant

Tait, Servant

CLIC Study Group

Conclusion

Dark Matter likely to be first signal of New Physics at TeV scale;

Current and future collider experiment programs at Tevatron, LHC and ILCto better define model constraints, discover signature of new phenomena beyond SM and measure them with enough accuracy to test their compatibilitywith both CMB satellite surveys and ground based DM searches;

If results would agree, major triumph for both Cosmology and Particle Physics, detailed data on DM particle would enable precise studies of Cosmology;

Detailed event reconstruction, more than maximum centre-of-mass energy is key to obtain accelerator experiment data with accuracy needed to match that of satellite experiments and emphasis the importance of the ILC programcomplementing the LHC in this new scientific adventure.