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The dark connection between Canis Major, Monoceros Stream,

The dark connection between Canis Major, Monoceros Stream, gas flaring, the rotation curve and the EGRET excess. Ingredients to this analysis. From EGRET excess of diffuse Galactic gamma rays Determination of WIMP mass Determination of WIMP halo (= standard halo + DM ring)

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The dark connection between Canis Major, Monoceros Stream,

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  1. The dark connection between Canis Major, Monoceros Stream, gas flaring, the rotation curve and the EGRET excess Ingredientsto this analysis • From EGRET excess of diffuse • Galactic gamma rays • Determination of WIMP mass • Determination of WIMP halo • (= standard halo + DM ring) • Confirmation of DM ring: • Rotation curve • N-body similation of • Canis Major/Monoceros stream • Gas flaring • PREDICTIONS • for LHC (if SUSY) • for direct searches • for solar neutrinos Rotation curve Doughnut of stars at 13 kpc Doughnut of H2 at 4 kpc Gas flaring Astronomers Cosmics Gamma rays Astrophysics 23%DM, thermal history of WIMPs annihilation cross section Galaxy formation Cosmology gamma spectra for BG + DMA SUSY Particle Physics

  2. T>>M: f+f->M+M; M+M->f+f T<M: M+M->f+f T=M/22: M decoupled, stable density (when annihilation rate  expansion- rate,i.e. =<v>n(xfr)  H(xfr) !) Thermal History of WIMPs Thermal equilibrium abundance Actual abundance Comoving number density WMAP -> h2=0.1130.009 -> <v>=2.10-26 cm3/s DM increases in Galaxies: 1 WIMP/coffee cup 105 <ρ>. DMA (ρ2) restarts again.. Annihilation into lighter particles, like quarks and leptons -> 0’s -> Gammas! T=M/22 Only assumption in this analysis: WIMP = THERMAL RELIC! x=m/T Jungmann,Kamionkowski, Griest, PR 1995

  3.   f f f ~ f A Z    f f f   W Z 0    Z W Example of DM annihilation (SUSY) ≈37 gammas Quark-Fragmentation known! Hence spectra of positrons, gammas and antiprotons known! Relative amount of ,p,e+ known as well. Dominant  +   A  b bbar quark pair Sum of diagrams should yield <σv>=2.10-26 cm3/s to get correct relic density

  4. Conclusion sofar IF DM particles are thermal relics from early universe they can annihilate with cross section as large as <v>=2.10-26 cm3/s which implies an enormous rate of gamma rays from π0 decays (produced in quark fragmentation) (Galaxy=1040 higher rate than any accelerator) Expect large fraction of energetic Galactic gamma rays to come from DMA in this case. Remaining ones from pCR+pGAS-> π0+X, π0->2γ This means: Galactic gamma rays have 2 components with a shape KNOWN from the 2 BEST studied reactions in accelerators: background known from fixed target exp. DMA known from e+e- annihilation (LEP)

  5. EGRET on CGRO (Compton Gamma Ray Observ.)Data publicly available from NASA archive Instrumental parameters: Energy range: 0.02-30 GeV Energy resolution: ~20% Effective area: 1500 cm2 Angular resol.: <0.50 Data taking: 1991-1994 Main results: Catalogue of point sources Excess in diffuse gamma rays

  6. R bulge disc Sun Basic principle for indirect dark matter searches From rotation curve: mv2/r=GmM/r2=cons. and (M/r)/r2 1/r2 for const. rot.curve EXPECT MOST OF DM IN CENTRE OF GALAXY Divergent for r=0? NFW profile1/r Isothermal profile const.  1/(r2+a2) R1 Sun disc R IF FLUX AND SHAPE MEASURED IN ONE DIRECTION, THEN FLUX ANDSHAPE FIXED IN ALL (=180) SKY DIRECTIONS for a given halo profile! THIS IS AN INCREDIBLE CONSTRAINT, LIKE SAYING I VERIFY THE EXCESS AND WIMP MASS WITH 180 INDEPENDENT MEAS.

  7. Background + signal describe EGRET data! WdB, C. Sander, V. Zhukov, A. Gladyshev, D. Kazakov, EGRET excess of diffuse Galactic Gamma Rays as Tracer of DM, astro-ph/0508617, A&A, 444 (2005) 51

  8. Analysis of EGRET data in 6 sky directions C: outer Galaxy A: inner Galaxy B: outer disc Total 2 for all regions :28/36  Prob.= 0.8 Excess above background > 10σ. E: intermediate lat. F: galactic poles D: low latitude A: inner Galaxy (l=±300, |b|<50) B: Galactic plane avoiding A C: Outer Galaxy D: low latitude (10-200) E: intermediate lat. (20-600) F: Galactic poles (60-900)

  9. Fits for 180 instead of 6 regions 180 regions: 80in longitude  45 bins 4 bins in latitude  00<|b|<50 50<|b|<100 100<|b|<200 200<|b|<900  4x45=180 bins  >1400 data points. Reduced 2≈1 with 7% errors BUT NEEDED IN ADDITION to 1/r2 profile, substructure in the form of 2 doughnut-like rings in the Galactic disc! ONE RING COINCIDES WITHORBIT FROM CANIS MAJORDWARF GALAXY which loses mass along orbit by tidal forces OTHER RING coincides with H2 ring

  10. Expected Profile Observed Profile z xy xy Rotation Curve 2002,Newberg et al. Ibata et al, Crane et al. Yanny et al. x y totalDM 1/(r2+a2) halo disk R xz xz bulge Inner Ring Outer Ring 1/r2 profile and rings determined from inde-pendent directions Normalize to solar velocity of 220 km/s Dark Matter distribution abg v2M/r=cons. (M/r)/r2 1/r2 for const. rotation curve Divergent for r=0? NFW1/r Isotherm const. 1/(r2+a2) Halo profile

  11. N-body simulations show: Progenitor of 13 kpc ring = Canis Major Dwarf just below Galactic disc

  12. Canis Major Dwarf orbits from N-body simulations to fit visible ring of stars at 13 and 18 kpc Movie from Nicolas Martin, Rodrigo Ibata http://astro.u-strasbg.fr/images_ri/canm-e.html Canis Major leaves at 13 kpc tidal stream of gas(106 M☉ from 21 cm line), stars (108 M☉ ,visible), dark matter (1010 M☉, EGRET)

  13. N-body simulation from Canis-Major dwarf galaxy retrograde prograde R=13 kpc Observed stars Canis Major (lat=-150) • Predicted DM ring from N-body • simulations, relying only on stars, • COINCIDED PERFECTLY • with EGRET excess: • radius of ring 13 kpc • ellipticity = 0.9 • angle of major axis -200 • retrograde orbit excluded Penarrubia et al. astro-ph/0410448   astro-ph/0703601  

  14. Dark matter signal (arb. units) lat. lat. CM Excess of DM from Canis Major +tidal stream indeed seen Factor 3 more signal from region with trailing stream (from comparison of data below and above Galactic disk)

  15. P M W Kalberla, L Dedes, J Kerp and U Haud, http://arxiv.org/abs/0704.3925 no ring with ring Gas flaring in the Milky Way Gas flaring needs EGRET ring!

  16. H2 Inner Ring coincides with ring of dust and H2 -> gravitational potential well! 4 kpc coincides with ring of neutral hydrogen molecules! H+H->H2 in presence of dust-> grav. potential well at 4-5 kpc. Enhancement of inner (outer) ring over 1/r2 profile 6 (8). Mass in rings 0.3 (3)% of total DM

  17. Does antiproton data exclude interpretation of EGRET data? Bergstrom et al. astro-ph/0603632, Abstract: we investigate the viability of the model using the DarkSUSY package to compute the gamma-ray and antiproton fluxes. We are able to show that their (=WdB et al) model is excluded by a wide margin from the measured flux of antiprotons. • Problem with DarkSUSY (DS): • Flux of antiprotons/gamma in DarkSUSY: O(1) from DMA. • However, O(10-2) from LEP data • Reason: DS has diffusion box with isotropic diffusion -> • DMA fills up box with high density of antiprotons • 2) More realistic models have anisotropic diffusion. • E.g. spiral galaxies have magnetic fields perpendicular to • disk-> antiprotons may spiral quickly out of Galaxy. • In addition: convection of particles by CR pressure.

  18. Preliminary results from GALPROP with isotropic and anisotropic propagation Antiprotons B/C ratio Summary: with anisotropic propagation you can send charged particles whereever you want and still be consistent with B/C and 10Be/9Be

  19. Astrophysicists: What is the origin of “GeV excess” of diffuse Galactic Gamma Rays? Astronomers: Why a change of slope in the galactic rotation curve at R0 ≈ 11 kpc? Why ring of stars at 13 kpc? Why ring of molecular hydrogen at 4 kpc? Why S-shape in gas flaring? Cosmologists: How is DM annihilating?A: into quark pairs How is Cold Dark Matter distributed? Particle physicists: Is DM annihilating as expected in Supersymmetry? 8 Physics Questions answered SIMULTANEOUSLY if WIMP = thermal relic A: DM annihilation A: DM substructure A: standard profile + substructure A: Cross sections perfectly consistent with mSUGRA for light gauginos, heavy squarks/sleptons

  20. Expected SUSY mass spectra in mSUGRA mSUGRA: common masses m0 and m1/2 for spin 0 and spin ½ particles

  21. Gauge unification perfect with SUSY spectrum from EGRET SM SUSY Update from Amaldi, dB, Fürstenau, PLB 260 1991 NO FREE PARAMETER With SUSY spectrum from EGRET + WMAP data and start values of couplings from LEP data perfect gauge coupling unification! Also b->s and g-2 agree within 2σ with SUSY spectrum from EGRET

  22. SUN CDMS EGRET? EGRET Solar neutrinos and direct DM detection

  23. Clustering of DM An artist picture of what we should see if our eyes were sensitive to 3 GeV gamma rays and we were flying with 220 km/s through the DM halo

  24. Objections from: • Astronomers: RC shows we have no DM in Galaxy • Astroparticle physicists: tune CR spectra to avoid • such “exotic” explanations as DM annihilation • But strong breaks in injection spectra needed • and no good fit if all 180 sky directions considered • Cosmologists: such high ringlike overdensities unlikely • Particle physicists: you discover new particles • at accelerators, not by watching the sky • Conventional models CANNOT explain simultaneously: • spectrum of gamma rays in ALL directions, • 1/r2 profile of excess, • shape of rotation curve, • ghostly ring of stars at 13 kpc, • ring of H2 at 4 kpc, • gas flaring

  25. Summary >10σ EGRET excess shows intriguing hint that: WIMP is thermal relic with expected annihilation into quark pairs DM becomes visible by gamma rays from fragmentation (30-40 gamma rays of few GeV pro annihilation from π0 decays) Results rather model independent, since only KNOWN spectral shapes of signal and background used, NO model dependent calculations of abs.fluxes. Different models or unknown experimental problems may change boost factor and/or WIMP mass, BUT NOT the distribution in the sky. SPATIAL DISTRIBUTION of annihilation signal is signature for DMA which clearly shows that EGRET excess is tracer of DM by fact that one can CONSTRUCT ROTATION CURVE FROM GAMMA RAYS. DM interpretation strongly supported N-body simulation of Canis Major dwarf and its tidal streams coinciding with the EGRET excess EGRET shows lots of DM mass in the tidal streams -> GAS FLARING

  26. Summary on WIMP searches Indirect detection:(SPACE EXPERIMENTS) intriguing hint for signals from DMA for 60 GeV WIMP from gamma rays Direct detection:(UNDERGROUND OBSERVATORIES) expected to observe signal in near future IF we are not in VOID of clumpy DM halo Direct production:(ACCELERATORS (LHC 2008-2018)): cannot produce WIMPs directly (too small cross section), BUT IF WIMPs are Lightest Supersymmetric Particle (LSP) THEN WIMPs observable in DECAY of SUSY particles IF EVERY METHOD measures SAME WIMP mass, then PERFECT. In this case Dark Matter is the supersymmetric partner of the CMB!

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