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Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 1 The dark connection between Canis Major, Monoceros Stream, gas flaring, the rotation curve.

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Presentation on theme: "Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 1 The dark connection between Canis Major, Monoceros Stream, gas flaring, the rotation curve."— Presentation transcript:

1 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 1 The dark connection between Canis Major, Monoceros Stream, gas flaring, the rotation curve and the EGRET excess 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 Ingredients to this analysis gamma spectra for BG + DMA SUSY Particle Physics Cosmology Astrophysics 23%DM, thermal history of WIMPs annihilation cross section Galaxy formation Cosmics Gamma rays Astronomers Rotation curve Doughnut of stars at 13 kpc Doughnut of H 2 at 4 kpc Gas flaring

2 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 2 Thermal History of WIMPs Thermal equilibrium abundance Actual abundance T=M/22 Comoving number density x=m/T Jungmann,Kamionkowski, Griest, PR 1995 WMAP ->  h 2 =0.113  0.009 -> =2.10 -26 cm 3 /s DM increases in Galaxies:  1 WIMP/coffee cup  10 5. DMA (  ρ 2 ) restarts again.. T>>M: f+f->M+M; M+M->f+f T f+f T=M/22: M decoupled, stable density (when annihilation rate  expansion- rate, i.e.  = n  (x fr )  H(x fr ) !) Annihilation into lighter particles, like quarks and leptons ->  0 ’s -> Gammas! Only assumption in this analysis: WIMP = THERMAL RELIC!

3 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 3 Example of DM annihilation (SUSY) Dominant  +   A  b bbar quark pair Sum of diagrams should yield =2.10 -26 cm 3 /s to get correct relic density Quark-Fragmentation known! Hence spectra of positrons, gammas and antiprotons known! Relative amount of ,p,e+ known as well.           f f f f f f Z Z W W  00 f ~ AZ ≈37 gammas

4 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 4 IF DM particles are thermal relics from early universe they can annihilate with cross section as large as =2.10 -26 cm 3 /s which implies an enormous rate of gamma rays from π 0 decays (produced in quark fragmentation) (Galaxy=10 40 higher rate than any accelerator) Expect large fraction of energetic Galactic gamma rays to come from DMA in this case. Remaining ones from p CR +p GAS -> π 0 +X, π 0 ->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) Conclusion sofar

5 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 5 Instrumental parameters: Energy range: 0.02-30 GeV Energy resolution: ~20% Effective area: 1500 cm 2 Angular resol.: <0.5 0 Data taking: 1991-1994 Main results: Catalogue of point sources Excess in diffuse gamma rays EGRET on CGRO (Compton Gamma Ray Observ.) Data publicly available from NASA archive

6 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 6 R Sun disc Basic principle for indirect dark matter searches R Sun bulge disc From rotation curve: mv 2 /r=GmM/r 2 =cons. and  (M/r)/r 2  1/r 2 for const. rot.curve EXPECT MOST OF DM IN CENTRE OF GALAXY Divergent for r=0? NFW profile  1/r Isothermal profile const.  1/(r 2 +a 2 ) IF FLUX AND SHAPE MEASURED IN ONE DIRECTION, THEN FLUX AND SHAPE FIXED IN ALL (=180) SKY DIRECTIONS for a given halo profile! R1R1 THIS IS AN INCREDIBLE CONSTRAINT, LIKE SAYING I VERIFY THE EXCESS AND WIMP MASS WITH 180 INDEPENDENT MEAS.

7 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 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 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 8 Analysis of EGRET data in 6 sky directions A: inner Galaxy (l=±30 0, |b|<5 0 ) B: Galactic plane avoiding A C: Outer Galaxy D: low latitude (10-20 0) E: intermediate lat. (20-60 0 ) F: Galactic poles (60-90 0 ) A: inner Galaxy B: outer disc C: outer Galaxy D: low latitude E: intermediate lat.F: galactic poles Total  2 for all regions :28/36  Prob.= 0.8 Excess above background > 10σ.

9 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 9 Fits for 180 instead of 6 regions 180 regions: 8 0 in longitude  45 bins 4 bins in latitude  0 0 <|b|<5 0 5 0 <|b|<10 0 10 0 <|b|<20 0 20 0 <|b|<90 0  4x45=180 bins  >1400 data points. Reduced  2 ≈1 with 7% errors BUT NEEDED IN ADDITION to 1/r 2 profile, substructure in the form of 2 doughnut-like rings in the Galactic disc! ONE RING COINCIDES WITH ORBIT FROM CANIS MAJOR DWARF GALAXY which loses mass along orbit by tidal forces OTHER RING coincides with H 2 ring

10 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 10 R x y z 2002,Newberg et al. Ibata et al, Crane et al. Yanny et al. 1/r 2 profile and rings determined from inde- pendent directions xy xz Expected Profile v 2  M/r=cons.  (M/r)/r 2  1/r 2 for const. rotation curve Divergent for r=0? NFW  1/r Isotherm const.  1/(r 2 +a 2 ) Dark Matter distribution Halo profile Observed Profile xy xz Outer Ring Inner Ring bulge totalDM 1/(r 2 +a 2) halo disk Rotation Curve Normalize to solar velocity of 220 km/s abg

11 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 11 N-body simulations show: Progenitor of 13 kpc ring = Canis Major Dwarf just below Galactic disc

12 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 12 Canis Major Dwarf orbits from N-body simulations to fit visible ring of stars at 13 and 18 kpc Canis Major leaves at 13 kpc tidal stream of gas(10 6 M ☉ from 21 cm line), stars (10 8 M ☉,visible), dark matter (10 10 M ☉, EGRET) Movie from Nicolas Martin, Rodrigo Ibata http://astro.u-strasbg.fr/images_ri/canm-e.html

13 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 13 N-body simulation from Canis-Major dwarf galaxy prograde retrograde Observed stars R=13 kpc Canis Major (lat=-15 0 ) 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 -20 0 retrograde orbit excluded Penarrubia et al. astro-ph/0410448 astro-ph/0703601

14 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 14 Excess of DM from Canis Major +tidal stream indeed seen Dark matter signal (arb. units) CM lat. Factor 3 more signal from region with trailing stream (from comparison of data below and above Galactic disk)

15 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 15 Gas flaring in the Milky Way no ring with ring P M W Kalberla, L Dedes, J Kerp and U Haud, http://arxiv.org/abs/0704.3925 Gas flaring needs EGRET ring!

16 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 16 Enhancement of inner (outer) ring over 1/r 2 profile 6 (8). Mass in rings 0.3 (3)% of total DM Inner Ring coincides with ring of dust and H 2 -> gravitational potential well! H2H2 4 kpc coincides with ring of neutral hydrogen molecules! H+H->H 2 in presence of dust-> grav. potential well at 4-5 kpc.

17 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 17 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): 1)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. Does antiproton data exclude interpretation of EGRET data?

18 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 18 Antiprotons B/C ratio Preliminary results from GALPROP with isotropic and anisotropic propagation Summary: with anisotropic propagation you can send charged particles whereever you want and still be consistent with B/C and 10 Be/ 9 Be

19 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 19 8 Physics Questions answered SIMULTANEOUSLY if WIMP = thermal relic 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 R 0 ≈ 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? A: DM substructure A: DM annihilation A: standard profile + substructure A: Cross sections perfectly consistent with mSUGRA for light gauginos, heavy squarks/sleptons

20 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 20 Expected SUSY mass spectra in mSUGRA mSUGRA: common masses m 0 and m 1/2 for spin 0 and spin ½ particles

21 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 21 Gauge unification perfect with SUSY spectrum from EGRET With SUSY spectrum from EGRET + WMAP data and start values of couplings from LEP data perfect gauge coupling unification! Update from Amaldi, dB, F ü rstenau, PLB 260 1991 SM SUSY Also b->s  and g-2 agree within 2σ with SUSY spectrum from EGRET NO FREE PARAMETER

22 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 22 Solar neutrinos and direct DM detection EGRET? CDMS SUN EGRET

23 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 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 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 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/r 2 profile of excess, shape of rotation curve, ghostly ring of stars at 13 kpc, ring of H 2 at 4 kpc, gas flaring

25 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 25 Summary >10σ EGRET excess shows intriguing hint that: WIMP is thermal relic with expected annihilation into quark pairs 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 becomes visible by gamma rays from fragmentation (30-40 gamma rays of few GeV pro annihilation from π 0 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. 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 Wim de Boer, Karlsruhe PPC2007, Texas A&M Univ., May. 16, 2007 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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