Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DarK Matter Annihilation In Clumpy Halos DarK Matter Annihilation In Clumpy Halos Collaboration with: Dominik Elsässer Acknowledgements: Matthias Steinmetz et al. (AIP Potsdam) ART code N-body simulations Joakim Edsjö (ANI Stockholm) DARKSUSY Stefan Hofmann (PI Toronto) Transfer function for WIMPs Tanja Kneiske (U Adelaide) EGB due to blazars Olaf Reimer (U Stanford) EGB from EGRET Aldo Morselli (INFN Roma) Multi-messenger

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore New Twist Consistent Model Follow-Up Elsässer & Mannheim, PRL 94, 1302 (2005) Elsässer & Mannheim, Astropart. Phys. 22, 65 (2004)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore: I. cold dark matter DMA Folklore: I. cold dark matter Cosmological structure formation  CDM = 0.23 Dark matter in Abell cluster (from gravitational lensing data) Ostriker (2004) Cl (credit: J.-P- Kneib/ESA)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore: II. Lee-Weinberg Criterion DMA Folklore: II. Lee-Weinberg Criterion Thermal history of Universe  WIMPs (  A ~pb, m  ~0.1-1TeV) freeze out at CDM density  CDM ~ -1 Weakly interacting massive particles at ~200 GeV are generic cold dark matter Turner 1992

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore: III. Neutralino as WIMP DMA Folklore: III. Neutralino as WIMP Lightest stable particle in R-parity conserving supersymmetry (neutralino): color singlet at electroweak scale with m  ~ 2 -1/4 G F -1/2 = 246 GeV Long-believed smoking gun! but… GLAST brochure Goebel 2004

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore: IV. Secondary gamma rays from High density regions DMA Folklore: IV. Secondary gamma rays from High density regions Clumpy dark matter halo Numerical limitation ~ 10 6 M  Stoehr et al Attractor in nonlinear simulations: NFW profile (  =1) Galaxy cluster Abell 85: simulation vs. observation Cusp 2 Durett et al. 2006

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore: V. Galactic Center shows Too hard spectrum DMA Folklore: V. Galactic Center shows Too hard spectrum 2 MAGIC/HESS observe SgrA* as steady source with hard power law above ~100 GeV J. Albert et al., ApJ Letters 638, L101 (2006)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop DMA Folklore: VI. Resume DMA Folklore: VI. Resume Smoking-gun line feature at 100 GeV – 1 TeV not seen from Galactic Center (neither from M87) -Loop-suppressed  or Z  flux actually expected -Continuum flux from bb or WW peaks at GeV -Relevant energy range currently inaccessible -Will open up with GLAST, HESS-II, and MAGIC-II Contribution to extragalactic background as inferred from EGRET data up to ~100 GeV -Expected to be small (Ullio et al. 2002; Ando 2005) -Extragalactic background: power law (Sreekumar et al. 98) -Galactic halo component of unknown origin with possible DMA connection (Dixon et al. 98, de Boer et al. 2003)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop New Twist: I. Extragalactic gamma ray Background from EGRET New Twist: I. Extragalactic gamma ray Background from EGRET Improved foreground model (GALPROP) removes enigmatic Galactic halo component and leads to new EGB spectrum (Strong, Moskalenko, and Reimer 2004) EGB shows excess above 1 GeV (from power law dN/dE~E ) Blazars IACT sensitivity: ~1000 high- peaked blazars expected ~50 13 known VHE blazars as of 2006 (ECRC 2006) EGRET >100 MeV

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Example of new type of high-peaked blazars which contribute to the EGB Example of new type of high-peaked blazars which contribute to the EGB New HBL at high redshift z=0.182 discovered at 100 GeV (Albert et al., 2006, ApJ Lett. 642, L119)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Extragalactic Particle Accelerators – High Peaked BL Lacertae Objects published detections Discovery fraction of X-ray bright high-peaked blazars (MAGIC 20h / source) ~ 30% 200 high-peaked blazars extrapolated from X-ray catalogues / 3 ~ 70 consistent with  =2.33 extrapolation of sub-GeV EGB Positions of >10 GeV photons poorly correlated with positions of known blazars (Thompson & Gehrels 2002) Thus: strong cosmological source of >GeV photons needed

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Extragalactic gamma ray background contribution from HBLs based on the X-ray luminosity function of Beckmann (2003) EGRET-type blazars HBLs Kneiske & Mannheim, ApJ (2006) submitted Excess in EGB still remains! Kneiske & Mannheim (2006)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop New Twist: II. Halo Substructure New Twist: II. Halo Substructure Power spectra of SUSY-CDM (Green, Hofmann, & Schwarz 2004) Small scale DM clumps down to M  at a scale of 0.02 pc Collisional damping and free streaming smear out inhomogeneities at still smaller scales Full range of structures M  – M  not resolvable with current computing resources (Diemand, Moore, & Stadel 2005)  Large boost factor for DMA emission (~  2 ds)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop New Twist: III. Cusp removal New Twist: III. Cusp removal Cusps can be destroyed by star formation feedback in high-z dwarfs (building blocks of galaxies) Merger evolution of galaxies preserves core structure (Kravtsov & Gnedin 2002) Small scale clumps may also be destroyed by tidal interactions with the gaseous disks (Silk et al.)  DMA signal of galaxy cores much weaker than signal from cluster cores Dwarfs Giants, Clusters Mashenko et al., Nature 442, 539 (2006)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop New Twist: IV. Other issues relevant for DMA New Twist: IV. Other issues relevant for DMA Co-annihilation relaxes relation between  A and  DM (Baltz et al. 2006) Anisotropy due to local clumps in DM halo (Elsässer & Mannheim 2004, Ando & Komatsu 2006) possible „smoking gun“ Problems with direct detection outside of clump Detection of clumps from galactic halo with GLAST challenging (Pieri, Branchini, & Hofmann 2006) Spikes around IMBHs (Bertone et al. 2005) Positron excess measured by HEAT may be a hint for high-mass DMA (Edsjo 2002) Synchrotron photon excess measured by WMAP („haze“) can be consistently explained by DMA (Finkbeiner 2004) Baltz, Edsjö, Freese & Gondolo, Phys. Rev. D 65, (2002) Coutou (2002) Tarle (2002) Kane, Wang, Wells (2001, 2002)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Consistent Model: I. DMA Model for EGB above 1 GeV Consistent Model: I. DMA Model for EGB above 1 GeV Elsässer & Mannheim, PRL (2005)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Consistent Model: II. Galactic Center Consistent Model: II. Galactic Center Consistent with EGRET/HESS/MAGIC non-detection due to energy gap! Cf. Ando (PRL 2005): (i) fluxes for 100 GeV and 1 TeV WIMPs avoiding the energy gap (ii) no clumping Other consistency checks: Direct detection Radio background Diffuse gal. gamma rays Antiprotons/Positrons WMAP foreground Muon magnetic moment Relic density  =10 -3 sr

Severe problems for DMA identification: (i) cusp depletion (ii) clump disruption (iii) stellar-origin source confusion Radial profile of signal strength X – Ray image (Chandra) Follow up: I. Galactic Center ( HESS-II, GLAST) Follow up: I. Galactic Center ( HESS-II, GLAST)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Follow-up: II. Center of Virgo Cluster (MAGIC-II, GLAST) Follow-up: II. Center of Virgo Cluster (MAGIC-II, GLAST)

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop M87 – Center of Virgo Cluster MAGIC Key Project

M 87 / Virgo Cluster C=40 C=335 Targeted observations seem promising with new – generation experiments DarkSusy scan Control astrophysical backgrounds: -AGN in M87 -CRp – interactions -MAGIC observations have started in May 2005

Gamma rays from the Dark Matter halo of M87 ART Code (A. Klypin et al.) solar masses; 9 million particles („Virgo Cluster“) (sub)structure down to solar masses D. Elsaesser, S. Gottloeber, A. Khalathyan and M. Steinmetz Gamma ray production rate depends on the line of sight integral  2 DM ds  Clumping should lead to a signal detectable by MAGIC

M87 Spectral Energy Distribution (ICRC) 2006

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Gold-plated DMA signature in M87 at ~50 GeV: (i) Steady, soft spectrum (ii) clumpy morphology in FOV Gold-plated DMA signature in M87 at ~50 GeV: (i) Steady, soft spectrum (ii) clumpy morphology in FOV 2nd telescope MAGIC-II in construction: improved clone of MAGIC Stereo: improvement in terms of flux sensitivity, energy reconstruction and angular resolution stereo

Karl Mannheim: Dark Matter Annihilation in Clumpy Halos / DESY Theory Workshop Summary Clumpy structure of DM halos (12 orders of magnitude below current numerical simulations) boosts DMA rate Neutralino with a mass of ~520 GeV and ~ cm 3 s -1 provides consistent model for EGB above GeV energies Confirmation with next generation of gamma ray observatories feasible (GLAST, HESS-II, MAGIC-II) Investigate LHC signatures for neutralinos which can successfully match the constraints of the model (astrophysical scenario largely insensitive to detailed SUSY parameters)