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Candidates for dark matter and the ILC

Candidates for dark matter and the ILC. G. B é langer (LAPTH- Annecy). Outline. Dark matter a new particle? Dark matter@ colliders + astro/cosmo Supersymmetric dark matter Non-susy dark matter vector boson, right-handed neutrino, scalar. What is the universe made of?.

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Candidates for dark matter and the ILC

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  1. Candidates for dark matter and the ILC G. Bélanger (LAPTH- Annecy)

  2. Outline • Dark matter a new particle? • Dark matter@ colliders + astro/cosmo • Supersymmetric dark matter • Non-susy dark matter • vector boson, right-handed neutrino, scalar

  3. What is the universe made of? • Dark matter inferred from rotation curve of galaxy • In recent years : new precise determination of cosmological parameters • Data from CMB (WMAP) agree with the one from clusters and supernovae • Dark matter: 23+/- 4% • Baryons: 4+/-.4% • Dark energy 73+/-4% • Neutrinos < 1% • Dark matter dominates over visible matter • Dark matter : guide to New physics models?

  4. Open questions -link to new physics • What is symmetry breaking mechanism • Hierarchy problem – new physics • What is DM (new particle WIMP)? • Likely to be related to physics at weak scale • Same new physics at the weak scale can also solve EWSB • Many possible solutions – many possible DM candidates • What is Dark energy ? • rather related to Planck scale • Baryon asymmetry in the universe • Could also be explained with NP at weak scale (eg. electroweak baryogenesis and MSSM with CP violation) • Origin of neutrino mass

  5. Dark matter : a new particle? • Weakly interacting particle gives roughly the right annihilation cross section to have Ωh2 ~0.1 • Many candidates for weakly interacting neutral stable particles • best known is neutralino in SUSY • Other models with NP at TeV scale have candidates, only need some symmetry to ensure that lightest particle is stable: UED, Warped Xtra-Dim, Little Higgs… • Superweakly interacting particles might also work (gravitino)

  6. Colliders : probing new physics • If DM is new particle – can be produced at colliders (LHC, ILC) • What is mass scale – discovery reach • What are properties of DM • Determine the underlying model for NP at the weak scale + consistency checks of underlying model at high scale, • Determination of properties of new particles – how well this can be done is model dependent • From this deduce annihilation cross sections for dark matter • Prediction for relic density – compare with measurement, if “collider prediction” precise enough it mean - Testing underlying cosmological model • Also compute cross section for dark matter scattering on nuclei -> consistent with direct detection results ? • Information on velocity distribution of DM ….

  7. Cosmology Establish DM and Determination of Ωh2 - with PLANCK 2008 ~5% level Constrain PP models assuming ΛCDM cosmology Direct detection Establish that a new particle is DM + some information on the mass of DM Compatibility with NP scenario (SUSY or other) Active area, many experiments underway : Xenon – new results in 2007 – Caveats: assumption about local density and velocity distribution Uncertainties in nuclear matrix elements Indirect detection Active area - search for DM in different channels (photons, positrons, neutrinos) Compatibility with NP scenario Cosmology/Astroparticle

  8. DM candidates - examples • Models • Status of neutralino in mSUGRA -CMSSM • Other MSSM • UED • RH neutrino • Scalar • Constraints on models : expectations for mass scale and properties of DM • Prospects for LHC, ILC and astro (DD) - reach • In some cases : probing properties of DM candidates at colliders

  9. Neutralino LSP • Nature of neutralino influences annihilation cross-sections • “naturally” correct annnihilation cross-section • Bino with light sleptons – annihilation into fermions • Bino-Higgsino LSP (annihilation in W/t pairs + some coan) • “Fine-tuning” required • Annihilation near resonance (heavy or light Higgs –LEP constraints) • Sfermion coannihilation (stau or stop) • σ of DM too small but density is depleted by coannihilation processes • Only in beyond mSUGRA • Bino-wino LSP (WW + coannihilation) • Bino-wino-Higgsino LSP

  10. WMAP – constraining CMSSM • Studies with grid scan and fixed value of parameters (mt) show 4 different regions that are consistent with WMAP – somewhat fine-tuned model LSP is in general bino • Bino – LSP (LEP constraints) • Sfermion Coannihilation • Mixed Bino-Higgsino • Annihilation into W pairs • strong mt dependence • Resonance (Z, light/heavy Higgs) • LEP constraints for light Higgs/Z • Heavy Higgs at large tanβ (enhanced Hbb vertex)

  11. Colliders and direct detection • LHC • Good for discovery of coloured particles, squarks, gluinos < 2- 2.5 TeV • Sparticles in decay chains • Limited reach when all squarks heavy – only chargino/neutralino “light” (in CMSSM when LSP is mixed bino/Higgsino) • ILC – can exceed reach of LHC in large M0-“focus point” –χ+χ-, χ1χj • Direct and indirect detection • Good prospects for mixed bino/Higgsino Baer et al., hep-ph/0405210

  12. Direct detection - limits • Detect dark matter through interaction with nuclei in large detector • Often dominate by Higgs exchange diagram (except when squarks are light) • Higgsino component is necessary to have LSP coupling to Higgs – • Annihilation of LSP in W pairs enhanced for mixed bino/Higgsino – also favoured for indirect detection • Many experiments underway and planned • In 2007 – new results announced from Xenon (Gran-Sasso) best limit ~factor 6 better than CDMS (Ge,Si) Xenon,E. Aprile, Talk @ APS 2007

  13. MCMC fits to CMSSM • In CMSSM mt is important parameter strongly affects the position of the “focus point” region (DM properties are similar nevertheless – bino-Higgsino) also dependence on other SM parameters • Global fits including SM parameters (mb,mt,α, αS) and MCMC approach + Bayesian statistics • Markov chain Monte Carlo allow many parameters scans • Ωh2, b->sγ, Mw, sin2θWl,BS->μμ, (g-2 )μ+ LEP constraints • Allanach et al, hep-ph/0609295, arXiv:0705.0487 • Roszkowski, Trotta, Ruiz de Austri, arXiv:0705.2012 • Ellis et al. , arXiv:0706.0652 (χ2fit)

  14. CMSSM – MCMC fit Allanach et al, 07050487 • Favoured region is small M0-M1/2 (with stau coan) but focus and Higgs funnel also allowed at 95%CL • Either μ > 0 or μ<0 • With flat priors in μ-B : small M0-M1/2 favoured • Good prospects for SUSY at colliders • Dependence on priors – not enough direct signals

  15. “Mirage” unification • Mixed modulus-anomaly mediated SUSY breaking MM-AMSB • Apparent (mirage) unification of soft terms at scale Qmir (in minimal model 109 GeV but could even be above GUT scale) • KKLT: type IIB superstring compactification with fluxes • Kachru et al, hep-th/0301240 • MSSM soft terms and phenomenology explored • Choi et al, hep-th/0411066; Falkowski et al, hep-ph/0507110; Kitano et al; Baer et al, hep-ph/0607085 • Minimal model specified by 5 ½ parameters : gravitino mass, ratio of MM/AMSB, tan β ,location of fields in extra dimensions: modular weights (n) and gauge kinetic function indices (l) m3/2, α, tanβ, sign(μ) n, l

  16. DM in mirage unification • Gaugino unification at scale Qmir • In minimal model: • M3:M2:M1~ (1-0.3 α)g32 :(1+0.1 α) g22:(1+0.66 α) g12 • Shifts in gaugino masses at weak scale compared to CMSSM • E.g. smaller M3/M1 leads to smaller μ at weak scale –Higgsino LSP • Scenarios with • bino-Higgsino LSP – annihilation WW and tt • Bino LSP+ stop coannihilation or Higgs resonance • When M1~-M2 : mixed wino LSP and bino-wino coannihilation • A large fraction of parameter space can give correct relic density assuming conventional thermal production

  17. Mirage unification • Main mechanisms for relic density within WMAP range • Higgs funnel (6) • Higgsino LSP (5) • Bino-wino LSP (8) • LHC reach over full parameter space (only for this choice of parameters) • ILC covers bino-wino region misses part of A-funnel and Higgsino regions nm=1/2, nH=1 Baer, Park, Tata, Wang, hep-ph/0703024

  18. Probing cosmology using collider information • Within the context of a given model can one make precise predictions for the relic density at the level of WMAP(10%) and even PLANCK (3%) therefore test the underlying cosmological model. • Assume discovery SUSY/Higgs, precision from LHC? Precision for ILC? • Answer depends strongly on underlying NP scenario, many parameters enter computation of relic density, only a handful of relevant ones for each scenario – work is going on both for LHC and ILC • A few benchmark scenarios studied in detail • 1st step : CMSSM scenario that predict relic density in agreement with WMAP. • 2nd step : MSSM scenarios • Other scenarios

  19. One sample benchmark: SPS1a’ • bino+ stau coannihilation • Annihilation into fermions • Coannihilation with staus • Relevant parameters : LSP mass, couplings, slepton masses • stau-neutralino mass difference (for coannihilation processes – factor e -ΔM) M0=70, M1/2=250, A0=-300,tanβ=10

  20. LHC+ILC and SPS1A’ • Start with CMSSM then estimate error from LHC measurements+ vary all MSSM parameters within these errors • LHC: measure neutralino-stau mass difference + 3 neutralino masses • Nojiri et al hep-ph/0512204 • Also important to measure sfermion/ neutralino parameters and setting limits on Higgs, other coan. particles … • With better determination of stau and neutralino masses – ILC much better “prediction” of relic density. • Other CMSSM scenarios can be hard for LHC – ILC provide more precise measurements (when within reach) Baltz et al, hep-ph/0602187

  21. Colliders + direct detection • With measurements from LHC+ILC can we refine predictions for direct/indirect detection? YES • LCC1 (not exactly same as SPS1a’) relic density too high • Prediction for spin-independent cross-section • Observable by 2010 • Factor of 3 uncertainty, improves significantly at ILC1000 (heavy Higgs mass)

  22. Another example : Higgsino- LCC2 • If squarks are heavy difficult scenario for LHC • only gluino accessible, chargino/neutralino in decays • mass differences could be measured from neutralino leptonic decays, • Relic density of DM depend on parameters of neutralino, need to be determine at % level • Recent study shows that necessary precision cannot be reached • Light Higgsinos possibly many accessible states at ILC • chargino pair production sensitive to bino/Higgsino mixing parameter • Baltz, et al , hep-ph/0602187

  23. LHC+ILC+direct detection – LCC2 • Mixed bino-Higgsino LSP • Large spin-independent cross-section • Xenon best limit 3 10-8 pb • Ambiguities at LHC –ILC improves • Study of bino-Higgsino scenario at LHC within context of NUHM –Polesello et al (Les Houches07) –results to come soon • ILC – additional information in cases where hA is accessible?

  24. DM in UED • String theory and M theory : best candidate for consistent theory of quantum gravity and unification of all interactions • Xtra dim models solve the hierachy problem either with compactified dim on circles of radius R effectively lowering the Planck scale near EW scale or introducing large curvature (warped) • UED: flat Xdim , all fields propagate in the “bulk” • Each bulk field has tower of KK states , mn~n/R • Explain: • 3 families from anomaly cancellation • Dynamical EWSB • No rapid proton decay

  25. Vector boson DM – UED • UED : All SM field propagate through all dim. of space R~TeV-1 • KK parity for proton stability • Minimal UED: LKP is B (1), partner of hypercharge gauge boson (spin 1) • s-channel annihilation of LKP (gauge boson) typically more efficient than that of neutralino LSP • Compatibility with WMAPmeans rather heavy LKP, 500-900 GeV • Tait, Servant ( 2002 ) • Mostly relevant for multi-TeV colliders Kong, Matchev, hep-ph/0509119

  26. Right-handed Dirac neutrino • Typical framework: sterile Dirac neutrino under SM but charged under extra symmetry SU(2)R • Phenomenologically viable model with warped extra-dimensions and right-handed neutrino (GeV-TeV) as Dark Matter was proposed (LZP) • Agashe, Servant, PRL93, 231805 (2004) • Stability requires additional symmetry , but symmetry might be necessary for EW precision or for stability of proton • νR can couple to Z through ν’L- νR or Z-Z’ mixing –naturally small • Main annihilation channel – Z/Z’ exchange

  27. Direct detection : Dirac neutrino • Dirac neutrino: spin independent interaction dominated by Z exchange (vector-like coupling)  very large cross-section for direct detection • coupling ZνRνRcannot be too large • Current DM experiments already restricts νR to • ~MZ/2, ~MH/2 or M(νR) > 700GeV • Vectorial coupling : elastic scattering on proton << neutron • Direct detection is best way to probe this type of model • At colliders: signal for KK quarks (Dennis et al. hep-ph/071158) and/or Z’ and/or invisible Higgs – to be explore Z GB, Pukhov, Servant

  28. Scalar dark matter (singlet) • Extensions of SM Higgs sector that can affect Higgs phenomenology • Simplest extension : add scalar singlet to SM + discrete symmetry-> stable scalar • Singlet couples to Higgses –responsible for annihilation • Higgs exchange also gives spin-independent direct detection

  29. Scalar DM - • No resonance annihilation needed DD directly related to annihilation cross-section • Good prospects for direct detection • Colliders : singlet modify properties of Higgs decays, (invisible decay) • LHC can look for those, need high luminosity – ILC good probe of invisible Higgs • No early signs of NP at LHC, yet possible signal in Direct detection – ILC with invisible H could provide important info. Barger et al 0706.4311

  30. WIMPS GUT-scale models include string inspired models (e.g.moduli-dominated), AMSB, Split SUSY, Compressed SUSY, NUHM, mirage mediation

  31. Conclusions • Many models of SUSY or other NP with DM candidate in general motivated by EWSB problem • Mass of DM varies over a wide range • If LHC discover new particles, will give precious information on NP model and on potential DM candidate – some complementarity with direct/indirect detection • Precise measurements of properties of DM at LHC (in favourable cases) and especially at ILC can reduce (PP) uncertainty in prediction of relic density and/or cross-sections in direct/indirect detection –might even test cosmological model

  32. Decay chain Signal: jet +dilepton pair Can reconstruct four masses from endpoint of ll and qll In particular stau-neutralino mass difference Here Δm (NLSP-LSP) = 10.5GeV Mixing in the stau sector obtained from For LSP couplings need 3 masses (χ1χ2χ4) and assume tanβ Assume tanβ known + limit on heavy stau and on heavy Higgs Determination of parameters LHC : SPA1A .087 < ΩCDMh2<.138

  33. LHC and DM • How will LHC see dark matter? • Missing energy • Sample decay chain • What can LHC measure? • Mass differences (using endpoints) – percent level • Masses (endpoints +cross-sections + theory) more difficult – Lester,Parker, White ’05 • Some properties of particles: spin.. (Barr –hep-ph/0511115) • Reconstruct underlying model parameters especially if theoretical assumption White, hep-ph/0605065

  34. Non-universal gaugino masses • String inspired moduli-dominated : LSP has important wino component • Binetruy et al, hep-ph/0308047 • Non universal SUGRA, • Depending on the GUT scale relation between gaugino masses can find WMAP compatible region in all the M0-M1/2 plane • GB, Boudjema, Cottrant, Pukhov, Bertin,Nezri, Orloff, Baer, Belyaev, Birkedal-Hansen, Nelson, Mambrini, Munoz… • M1~M2 LSP is mixed bino-wino annihilation more efficient, scale of LSP ~ 500GeV M1=1.8M2|GUT mixed bino/wino Higgs exchange GB, et al, NPB706(2005)

  35. Non-universality • Many high scale models with non-universal gaugino masses and/or non-universal Higgs masses • Heterotic supersting with orbifold compactification, SUSY breaking dominated by moduli field • XtraDim SUSY GUT models, SUSY breaking via gaugino mediation • Pheno -motivated • Compressed SUSY : if M3<M2 at GUT scale, less fine-tuning to have small values of m2Hu – squarks not so heavy relative to LSP • Martin, PhysReVD74 (2007) 115005 • From DM point of view: in these models, easier to get LSP not pure bino --- • Can find WMAP compatible regions in all M0-M1/2 plane • Mixed bino-Higgsino LSP or mixed bino-wino LSP or even bino-wino-Higgsino LSP : annihilation efficent, scale of LSP can be several hundred GeV • Higgsino-LSP not necessarily associated with very heavy scalar spectrum and very heavy Higgs like in mSUGRA

  36. Non-universal Higgs masses • Motivated by SO(10) or SU(5) GUTs – Higgs fields in different representation than fermion field • μ smaller than in CMSSM –LSP bino/Higgsino (even at low M0) • Annihilation via Higgs resonance even when tanβ not large • Even when squarks are not as heavy as in CMSSM, ILC reach (chargino pair) can exceed that of LHC • ILC: when heavy Higgs not so heavy – ee->hA, H+H- • When μ small : also all neutralinos and charginos ILC ILC Baer et al hep-ph/0504001

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