Astroparticle physics Astronomy. Particle physics. Big Bang billion years 95% of energy in universe of unknown nature. 1 ps.

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1 Dark matter visible by hard gamma rays? Cosmology 13.7 billion years 95% of energy in universe of unknown nature Astroparticle physics Astronomy Particle physics 1 ps s Big Bang Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

2 Discovery of DM in 1933 Zwicky, Fritz ( Center of the Coma Cluster by Hubble space telescope Dubinski Zwicky notes in 1933 that outlying galaxies in Coma cluster moving much faster than mass calculated for the visible galaxies would indicate Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17, 2007 DM attracts galaxies with more force-> higher speed. But still bound! 2

3 Do we have Dark Matter in our Galaxy? Rotationcurve Solarsystem 1/ r rotation curve Milky Way Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

4 Estimate of DM density DM density falls off like 1/r 2 for v=const. Averaged DM density 1 WIMP/coffee cup (for 100 GeV WIMP) Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

5 What is known about Dark Matter? 95% of the energy of the Universe is non-baryonic 23% in the form of Cold Dark Matter From CMB + SN1a + surveys Dark Matter enhanced in Galaxies and Clusters of Galaxies but DM widely distributed in halo-> DM must consist of weakly interacting and massive particles -> WIMP s If it is not dark It does not matter Annihilation with <σv>= cm 3 /s, if thermal relic DM halo profile of galaxy cluster from weak lensing Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

6 Expansion rate of universe determines WIMP annihilation cross section Thermal equilibrium abundance Actual abundance Comoving number density T=M/22 T>>M: f+f->m+m; M+M->f+f T<M: M+M->f+f T=M/22: M decoupled, stable density (wenn Annihilationrate Expansionrate, i.e. Γ=<σv>nχ(x fr ) H(x fr )!) WMAP -> Ωh 2 =0.113± > <σv>= cm 3 /s DM increases in Galaxies: 1 WIMP/coffee cup 10 5 <ρ>. DMA ( ρ 2 ) restarts again.. Annihilation into lighter particles, like quarks and leptons -> π 0 s -> Gammas! Gary Steigmann ( x=m/t Only assumption in this analysis: WIMP = THERMAL RELIC! Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

7 Conclusion sofar IF DM particles are thermal relics from early universe they can annihilate with cross section as large as <σv>= 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 (+some IC+brems) 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) Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

8 Example of DM annihilation (SUSY) χ χ ~ f f f χ χ A f f χ χ Z f f χ χ χ W χ ± χ 0 W χ Z Z 37 gammas Dominant χ + χ A b bbar quark pair Sum of diagrams should yield <σv>= cm 3 /s to get correct relic density Quark fragmentation known! Hence spectra of positrons, gammas and antiprotons known! Relative amount of γ,p,e+ known as well. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

9 Basic principle for indirect dark matter searches From rotation curve: Forces: mv 2 /r=gmm/r 2 or M/r=const.for v=cons. and ρ (M/r)/r 2 ρ 1/r 2 for flat rotation curve Expect highest DM density IN CENTRE OF GALAXY Divergent for r=0? NFW profile 1/r Isotherm profile const. Sun Sun R 1 R bulge R disc disc IF FLUX AND SHAPE MEASURED IN ONE DIRECTION, THEN FLUX AND SHAPE FIXED IN ALL (=180) SKY DIRECTIONS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! THIS IS AN INCREDIBLE CONSTRAINT, LIKE SAYING I VERIFY THE EXCESS AND WIMP MASS WITH 180 INDEPENDENT MEAS. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

10 EGRET on CGRO (Compton Gamma Ray Observ.) Data publicly available from NASA archive Instrumental parameters: Energy range: GeV Energy resolution: ~20% Effective area: 1500 cm 2 Angular resol.: <0.5 0 Data taking: Main results: Catalogue of point sources Excess in diffuse gamma rays Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

11 Two results from EGRET paper Excess Called Cosmic enhancement Factor Enhancement in ringlike structure at kpc Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

12 Galactic coordinates: longitude l and latitude b < latitude b < < longitude l < ( l,b)=(0,0)=galactic Center ( l,b)=(0,90)=north Galactic Pole Galactocentric coordinates (left-handed to be corotating!) Mathematics usually right-handed! Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

13 Background + signal describe EGRET data! Background + DMA signal describe EGRET data! 50 GeV IC π 0 WIMPS Brems. π 0 IC WIMPS Brems. IC 70 Blue: background uncertainty Blue: WIMP mass uncertainty Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

14 What about background shape? No SM No SM Quarks from WIMPS Protons Electrons Quarks in protons Background from nuclear interactions (mainly p+p-> π 0 + X -> γ + X inverse Compton scattering (e-+ γ -> e- + γ) Bremsstrahlung (e- + N -> e- + γ + N) Shape of background KNOWN if Cosmic Ray spectra of p and e- known Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

15 PYTHIA processes: Contribution from various hadronic processes 11 f+f' -> f+f' (QCD) f+fbar -> f'+fbar' 0 13 f+fbar -> g + g 0 28 f+g -> f + g g+g -> g + g g+g -> f + fbar Single diffractive (XB) Single diffractive (AX) Double diffractive Low-pT scattering 0 Prompt photon production: 14 f+fbar -> g+γ 0 18 f+fbar -> γ +γ 0 29 f+g -> f +γ g+g -> g + γ g+g -> γ + γ 0 2 GeV 4 8 diff Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

16 Energy loss times of electrons and nuclei τ -1 = 1/E de/dt τ univ Protons diffuse much faster than energy loss time, so expect SAME shape everywhere. Indeed observed: outer Galaxy can be fitted with same shape as inner Galaxy. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

17 Analysis of EGRET Data in 6 sky directions A: inner Galaxy B: outer disc C: outer Galaxy Total χ 2 for all regions :28/36 Prob.= 0.8 Excess above background > 10σ. D: low latitude E: intermediate lat. F: galactic poles A: inner Galaxy (l=±30 0, b <5 0 ) B: Galactic plane avoiding A C: Outer Galaxy D: low latitude ( ) E: intermediate lat. ( ) F: Galactic poles ( ) Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

18 Fits for 180 instead of 6 regions 180 regions: 8 0 in longitude 45 bins 4 bins in latitude 0 0 < b < < b < < b < < b <90 0 4x45=180 bins >1400 data points. Reduced χ 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 Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

19 xy xz Expected Profile Dark Matter distribution v 2 M/r=cons. and ρ (M/r)/r 2 ρ 1/r 2 for const. xzrotation curve Divergent for r=0? NFW 1/r Isotherm const. Halo profile Observed Profile xy Rotation Curve x y 2002,Newberg et al. Ibata et al, Crane et al. Yanny et al. disk Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17, z bulge Inner Ring totaldm 1/r 2 halo Outer Ring 1/r 2 profile and rings determined from independent directions Normalize to solar velocity of 220 km/s

20 How does DM substructure form from tidal disruption of dwarf galaxies? Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

21 The local group of galaxies Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

22 The Milky Way and its 13 satellite galaxies Canis Major Tidal force F G 1/r 3 Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

23 Tidal streams of dark matter from CM and Sgt CM Sun Sgt From David Law, Caltech Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

24 Artistic view of Canis Major Dwarf just below Galactic disc Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

25 N-body simulation from Canis-Major dwarf galaxy Observed stars R=13 kpc,φ=-20 0,ε=0.8 Canis Major (b=-15 0 ) prograde retrograde Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

26 Gas flaring in the Milky Way P M W Kalberla, L Dedes, J Kerp and U Haud, no ring with ring Gas flaring needs EGRET ring with mass of M! Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

27 Inner Ring coincides with ring of dust and H 2 -> gravitational potential well! H 2 Enhancement of inner (outer) ring over 1/r 2 profile 6 (8). Mass in rings 0.3 (3)% of total DM 4 kpc coincides with ring of neutral hydrogen molecules! H+H->H 2 in presence of dust-> grav. potential well at 4-5 kpc. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

28 Do antiproton data exclude interpretation of EGRET data? Bergstrom et al. astro-ph/ , 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) Priors of DARKSUSY.(and other propagation models as well): a) static galactic magnetic fields are negligible b) gas is smoothly distributed c) propagation in halo and disk are the same ALL priors likely wrong and can change predictions for DM searches by ORDER OF MAGNITUDE (and still ok with all observations!) Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

29 Another propagation model including static magnetic fields and gas clouds and anisotropic diffusion it is shown that Galactic cosmic rays can be effectively confined through magnetic reflection by molecular clouds, Integral excess of positrons in bulge because positrons are trapped in magnetic mirrors between gas clouds? Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

30 The van Allen belts are trapped cosmic rays in magnetic mirrors of earth Radiation in inner belt: 25 Sv/yr inside space ship Lethal dose for human: 3 Sv/h Satellites switch of electronics, when entering dense radiation areas. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

31 Magnetic fields observed in spiral galaxies fieldline disk A few ug perpendicular to disc. Fast propagation out of halo! A few µg along spiral arms: Expected between molec.clouds Isotropic diffusion assumes randomly oriented magnetic turbulences. Preferred magnetic field directions -> anisotropic propagation Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

32 Escape time of cosmic rays and grammage (distance x density) B/C determines grammage 10 Be/ 9 Be determines escape time B/C=secondary/prim.determines grammage (smaller than disc!) In GALPROP: by large halo In CHANDRAN: by reflecting molecular clouds 10 Be (t 1/2 = 1.51 Myr) is cosmic clock: lifetime of cosmics 10 7 yrs. In GALPROP: by large halo In CHANDRAN: by long trapping. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

33 Preliminary results from GALPROP with isotropic and anisotropic propagation CHANDRAN model GALPROP model Summary: with fast propagation perp. to disc (e.g. by convection, fast diffusion or static magnetic fields) one reduces contribution of charged particles from DMA by large factor and can be consistent with B/C and 10 Be/ 9 Be Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

34 Comparing radioactive isotopes with positron distribution (Knödlseder et al.) 1809 kev ( 26 Al) 511 kev Problem: expect most low energy positrons to originate from radioactive nuclei with β+ decay. But these are distributed in bulge AND disk. Positrons mostly in bulge. Why??? Unknown positron source only in bulge?? Light DM? Or simply: relativistic positrons escape in disk and annihilate in bulge? Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

35 astro-ph/ NO annihilation in molecular clouds (MC), although 75% of mass in MC. Why? Either volume of MC too small OR MC are magnetic mirrors as postulated by Chandran! Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

36 What about Supersymmetry? Assume msugra 5 parameters: m 0, m 1/2, tanb, A, sign μ Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

37 EGRET excess interpreted as DM consistent with WMAP, Supergravity and electroweak constraints Stau coannihilation m A resonance Stau LSP Too large boostfactor for EGRET data Charginos, neutralinos and gluinos light h<114 Bulk EGRET WMAP LSP largely Bino DM may be supersymmetric partner of CMB Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

38 Gauge unification perfect with SUSY spectrum from EGRET SM SUSY Update from Amaldi, db, Fürstenau, PLB NO FREE parameter With SUSY spectrum from EGRET + WMAP data and start values of couplings from final LEP data perfect gauge coupling unification! Also b->sγ and g-2 in agreement with SUSY spectrum from EGRET Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

39 Grand Unified Theories Possible evolution of Universe Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

40 Indirect DM detection from solar neutrinos SUN Celestial bodies collect DM in their cores by their high density. Annihilation can result in flux of HIGH energy neutrinos from sun (from b-decays or from Z-decays). EGRET Neutrinos can be detected by large detectors,like Super-Kamiokande, Amanda, Ice-Cube, Baksan by the charged current interactions with nuclei,which yields muons in the detectors. Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

41 Direct Detection of WIMPs WIMPs elastically scatter off nuclei => nuclear recoils Measure recoil energy spectrum in target χ 0 H,Z χ 0 If SUSY particle spectrum known, elastic scattering X-section can be calculated EGRET? CDMS XENON10 Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

42 8 physics questions answered SIMULTANEOUSLY if WIMP = thermal relic Astrophysicists: What is the origin of GeV excess of diffuse Galactic Gamma Rays? A: DM annihilation Astronomers: Why a change of slope in the galactic rotation curve at R 0 11 kpc? A: DM substructure 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? substructure Particle physicists: Is DM annihilating as expected in Supersymmetry? A: standard profile + A: Cross sections perfectly consistent with msugra for light gauginos, heavy squarks/sleptons Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

43 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 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 shapes or unknown experimental problems may change the gamma ray flux 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 and tidal streams from gamma rays. DM interpretation strongly supported independently by gas flaring DM interpretation perfectly consistent with Supersymmetry Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,

44 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 )): 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! Wim de Boer, Karlsruhe Seminar IHEP, Beijing, August 17,