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Dark Matter

Dark Matter. Evidence Possibilities Detection ?. Mathieu Langer. (Many thanks to Gianfranco Bertone , Institut d’Astrophysique de Paris). Cosmological parameters : status. Combination of ‘independent’ data Universe spatially flat : ‘Cosmological Constant’ : ~ 0.7 ‘Matter’ : ~ 0.3

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Dark Matter

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  1. Dark Matter Evidence Possibilities Detection ? Mathieu Langer (Many thanks to Gianfranco Bertone, Institut d’Astrophysique de Paris)

  2. Cosmological parameters : status • Combination of ‘independent’ data • Universe spatially flat : ‘Cosmological Constant’ : ~ 0.7 ‘Matter’ : ~ 0.3 (rem : baryons ~ 0.04)

  3. First Evidence : Velocity dispersion of galaxies in clusters Coma cluster of Galaxies Fritz Zwicky, 1933 Motions require more than 100 times more mass than visible!

  4. Galactic rotation curves Vera Rubin, 1970s

  5. Rotation curves & Dark Matter Image UV GALEX, A. Gil de Paz, 2006

  6. Degeneracy : disc vs. halo DM • Mass/Luminosity ratio? (Stellar pop. synth.) • DM : density profile ? (simulations, poorly constrained at centre) Broeils, 1992, A&A

  7. Dark Matter : Clusters of galaxies again ROSAT X-Ray A 2029 NGC720 DSS optical

  8. Measure of a cluster density profile • Image : X emission • X emission is a function of density n, x ~ n2 • Question: What density profile can give the observed X ray emission ? Line: Best Fit Points: Observations Abell 2319 – Image ROSAT [millions of light years] • Procedure: • Identify the cluster centre • Average azimuthally X emission • Fit the emission profile • Deduce the required density

  9. Gravitational lensing (http://hubblesite.org) Convergence Convergence + shear

  10. Abell 2218

  11. First 3D map of DM distribution ! • High fidelity maps of DM distribution on large scales, resolved in angular resolution and depth thanks to the Cosmic Evolution Survey of the HST • (2 degrees2) • Shape of 71 galaxies per arcmin2 •  shear field •  total projected mass • Follow-up observations by VLT, Subaru, Cerro Tololo & Kitt Peak to get the redshifts Massey et al., Nature, 7 Janvier 2007

  12. “Direct proof” : the Bullet Cluster • Optical image of merging clusters (here: 1E 0657-558) • Reconstruct the shear and the convergence (grav. lensing) • Projected density maps • (green contours) 200 kpc Clowe et al. ApJL 2006

  13. “Direct proof” : the Bullet Cluster • X-ray image of the same cluster, 1E 0657-558, by Chandra • Green contours : convergence  (prop. to the projected density) • White contours : peaks of  at 68.3%, 95.5% and 99.7% C.L. 200 kpc Clowe et al. ApJL 2006  Presence of non-luminous gravitating mass !

  14. Matter census in the Universe 1% Stars 7% Gas in virialised structures Baryons 7% Warm/hot gas in IGM Don’t know what Dark Matter is? Ask a Particle Physicist! 85% DARK MATTER Non-baryonic

  15. Kaluza-Klein DM in UED Kaluza-Klein DM in RS Axion Axino Gravitino Photino SM Neutrino Sterile Neutrino Sneutrino Light DM Little Higgs DM Wimpzillas Cryptobaryonic DM Q-balls Mirror Matter Champs (charged DM) D-matter Cryptons Self-interacting Superweakly interacting Braneworld DM Heavy neutrino NEUTRALINO Messenger States in GMSB Branons Chaplygin Gas Split SUSY Primordial Black Holes … “WIMPs”! “Dark Matter” candidates L. Roszkowski

  16. WIMP : identity file • Full name : Weakly Interacting Massive Particle • Rem : generic name • Interactions : gravitational, weak nuclear (i.e. « weaker than weak » cross-sections) • Mass : high enough so as to be cold today • Life time : stable / sufficiently long to have remained until now • Relic density : Boltzmann equation + freeze-out • Nature?  SUSY?  KK Extra-dimensions?  New Physics!

  17. SUSY & LSP… • Supersymmetry? • Extension of the Poincaré algebra: Q |Boson = |Fermion , Q |Fermion = |Boson {Q, Q} P , [H,Q] = 0 • Unification of gauge couplings, mass hierarchy (Higgs) • Keep B & L conservation  R-parity, R = (-1)3B+L(-1)2S • SM particles : R = +1 SUSY particles : R = -1 • R-parity conservation ( if ) • Lightest Supersymmetric Particle stable! • “Natural” candidate for Dark Matter • MSSM + R-parity  Neutralino :

  18. Extra Universal Dimensions (EUD) • Kaluza-Klein : extra dimensions • EUD : all fields propagate in the 5th dim. Periodical conditions  Momentum quantification Compactification of extra dim. at each pt. of 3D space

  19. Dark Matter — related experiments: 2006 World Census Boulby Mine Soudan Mine Frejus Baikal LHC Sudbury Canfranc MILAGRO Gran Sasso Tevatron Antares STACEE Nestor VERITAS Nemo TIBET, ARGO-YBJ MAGIC TACTIC PACT GRAPES Neutrino Telescopes Observing Satellites Gamma-ray Telescopes (non-ACT) Gamma-ray Telescopes (ACTs) Direct Detection Exps. HESS CANGAROO Colliders PAMELA Fermi IceCube (South Pole) G. Bertone, Particle DM: what comes next?, Seminar @ Tuebingen U.

  20. EDELWEISS DAMA ZEPLIN CDMS Direct detection : Principle & Status  n Detector (bolometer) • Collision of a WIMP on a nucleus •  Light •  Heat •  Charge Background noise, cryogenics, …

  21. DM Indirect Detection • Gamma Telescopes • Ground (CANGAROO, HESS, MAGIC, MILAGRO, VERITAS) • Space : Fermi (GLAST) satellite • Future Cherenkov Telescope Array? • Neutrino Telescopes • Amanda, IceCube • Antares, Nemo, Nestor • Km3 • Antimatter Satellites • PAMELA • AMS-2 • Other • Synchrotron • SZ effect • Effects on stars… Indirect Detections

  22. Indirect detection : Dark Matter annihilations X = DARK MATTER SM = STANDARD MODEL PARTICLE Early Universe Today X SM X SM X SM X SM Rough estimate of the relic density: Electroweak-scale cross sections can reproduce correct relic density. LSP in SUSY scenarios KK DM in UED scenarios are OK!!

  23. -ray flux from the GC We can conveniently re-write the-ray flux from the GC as where J contains all information onAstrophysics and theDM profileis usually parameterised as Note : density profile at the very centre may be sharper due to central BH

  24. *Adiabatic* growth of a Black Hole: BHs as “Annihilation Boosters”! r- r-sp Conserve Mass & Angular Momentum: sp= 9-2 4-

  25. An intuitive description of Dark Matter “Spikes” Bertone & Merritt 2005

  26. Evidence for a Supermassive Black Hole at the Galactic Centre Genzel et al. 2003 M= 3.6 x 106Solar Masses

  27. AnnihilationRadiation SUSY (E. Nezri et al, 2001) To calculate the fluxes, details of annihilations are required. Neutralino annihilations cross-sections can be obtained numerically (DarkSUSY, microMEGA, etc.) UED (Servant & Tait, 2002) Servant & Tait obtained annihilation cross-sections for B(1) particles. In the non-relativistic limit, dependent only on the B(1) mass.

  28. -ray flux from the GC GB, Servant & Sigl, 2003 Predictions for KK dark matter and neutralinos in the case of a NFW profile without central spike. Fluxes are always below the EGRET normalisation, but within the reach of several future experiments. Possibility of constraining B(1) mass. Importance of the dark matter density profile. GB, Servant & Sigl 2003

  29. What about baryonic Dark Matter ??Black Holes? Brown Dwarves? Failed Stars?

  30. Baryonic Objects of stellar mass or lower (Afonso et al, A&A, 2003) No "MACHOs" in our Galaxy

  31. Toy derivation of scalar Lagrangian (J.Virzi, UC Berkeley) • Heuristic derivation showing how mass terms appear – infinite tower of KK modes

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