Dark Matter and Supersymmetry We don t know it, because we don t see it! 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 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 1
EGRET on CGRO (Compton Gamma Ray Observ.) Data publicly available from NASA archive 9 yrs of data taken in space! (1991-2000) W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 2
Thermal history of WIMPs as thermal relic Thermal equilibrium abundance Actual abundance Comoving number density T=M/22 x=m/t Jungmann,Kamionkowski, Griest, PR 1995 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 expansionrate, i.e. Γ=<σv>nχ(x fr ) H(x fr )!) WMAP -> Ωh 2 =0.113±0.009 -> <σv>=2.10-26 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! Only assumption in this analysis: WIMP = THERMAL RELIC! W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 3
R-Parity W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 4
R-Parity prevents proton decay R-Parity requires TWO SUSÝ particles at each vertex. Therefore proton decay forbidden, but DM annihilation (leading to indirect detection by observing stable annihilation products) and elastic scattering (leading to possible direct detection) possible. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 5
DM Annihilation in Supersymmetry 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>=2.10-26 cm 3 /s to get correct relic density Quark-Fragmentation known! Hence spectra of positrons, Gammas and antiprotons known! W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 6
The EGRET excess of diffuse galactic gamma rays without and with DM annihilation π 0 IC Brems π 0 IC WIMPS Brems Fit only KNOWN shapes of BG + DMA, i.e. 1 or 2 parameter fit NO GALACTIC models needed. Propagation of gammas straightforward If normalization free, only relative point-to-point errors of 7% important, not absolute normalization error of 15%. Statistical errors negligible. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 7
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 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 8
PYTHIA processes: Contribution from various hadronic processes 11 f+f' -> f+f' (QCD) 2370 12 f+fbar -> f'+fbar' 0 13 f+fbar -> g + g 0 28 f+g -> f + g 2130 68 g+g -> g + g 1510 53 g+g -> f + fbar 20 92 Single diffractive (XB) 1670 93 Single diffractive (AX) 1600 94 Double diffractive 700 95 Low-pT scattering 0 Prompt photon production: 14 f+fbar -> g+γ 0 18 f+fbar -> γ +γ 0 29 f+g -> f +γ 1 115 g+g -> g + γ 0 114 g+g -> γ + γ 0 2 GeV 4 8 diff. 16 32 64 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 9
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 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 10
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 (10-20 0) E: intermediate lat. (20-60 0 ) F: Galactic poles (60-90 0 ) W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 11
Conventional Model without DMA in 6 sky regions χ 2 of conventional model:663/42 Prob. = 0 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 12
Fits for 180 instead of 6 regions 180 regions: 80 in longitude 45 bins 4 bins in latitude 00< b <50 50< b <100 100< b <200 200< b <900 4x45=180 bins bulge disk sun W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 13
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 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 14 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
Rotation curve of Milky Way Honma & Sofue (97) Schneider &Terzian (83) Brand & Blitz(93) W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 15
Do other galaxies have bumps in rotation curves? Sofue & Honma W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 16
Possible origin of ring like structure Infall of dwarf galaxy in gravitational potential of larger galaxy into elliptical orbit start precessions, if matter is not distributed homogeneous. Tidal forces gradient of field, i.e. 1/r 3. This means tidal disruption only effective at pericenter for large ellipticity! Apocenter Pericenter Could tidal disruption of dwarf galaxy lead to ringlike structure of 10 10 solar masses? N-body simulations no clear answer. All depends on initial conditions. Also no clear explanation for ring of stars of 10 9 solar masses. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 17
Tidal disruption of satellite in potential of larger galaxy Hayashi et al., astro-ph/02003004 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 18
Basics of Astroparticle physics Flux of Gamma Rays of WIMP Annihilation in direction ψ: 2 Similar expression for: pp->π 0 +x->γγ+x, (ρ = Gas density, max. in disc) eγ->eγ, en->eγn, (ρ = Electron/Gamma density) Extragalactic background (isotrop) DM Annihilation (ρ 1/r 2 for flat rotation curve) All processes have different energy spectra. Cross sections known. Densities less well known, hence free normalzations for background and signal Normalization error: 15% for EGRET. Point-to-point error 7%. Only these are important if normalization free. ρχ=mχ nχ W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 19
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! Forms in presence of dust-> grav. potential well at 4-5 kpc. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 20
Halo profile without rings DISC 10 0 <b<20 0 5 0 <b<10 0 20 0 <b<90 0 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 21
Halo profile with rings DISC 10 0 <b<20 0 5 0 <b<10 0 20 0 <b<90 0 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 22
Alternative solution: Optimize e,p spectra to fit gammas Optimized Model from Strong et al. astro-ph/0406254 Electrons Protons B/C Nucleon and electron spectra tuned to fit gamma ray data. Have to assume we live in local Bubble. Production of secondary nuclei not described with same parameters. BUT gamma rays not well described either! W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 23
Optimized Model from Strong et al. astro-ph/0406254 Change spectral shape of electrons AND protons A: inner Galaxy B: outer disc C: outer Galaxy π 0 IC Brems D: low latitude E: intermediate lat. F: galactic poles χ 2 of optimized model:110/42 Prob. < 10-7 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 24
Fits for optimized Model including DM A: inner Galaxy B: outer disc C: outer Galaxy D: low latitude E: intermediate lat. F: galactic poles 3 Components: galactic background + extragalactic background + DM annihilation (with same WIMP mass and same boostfactor). Fit probability of optimized model improves from 10-7 -> 0.8 with DMA. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 25
From original paper on Optimized Model Strong et al. astro-ph/0406254 100 MeV 150 MeV 300 MeV 500 MeV 1000 MeV 2000 MeV longitude Real problem with conventional models: if data is perfectly fitted with sum of power spectrum+monoenergetic peak for quarks, then you cannot get good fit with whatever power spectrum you invent. In addition, DM has different spatial distribution, so fitting over all directions gives prob.<10-7 in all cases. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 26
Objections from astrophysicists Astrophysicists: cannot believe collisionless DM, i.e. particles which experience only gravity, is selfannihilating and that particle physicists even believe to know spectral shapes of final states! They prefer their local bubbles. Answer: too bad, but their local bubbles or optimized models do not work if one considers all sky directions W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 27
Objections from particle physicists Particle physicists: you assume spectrum of protons to be the same everywhere in galaxy. How can you be sure? Answers: 1) If centre of galaxy would be different because of SN there is no reason to get same shape of excess in outer galaxy (very few SN) 2) energy loss times > age of universe, very hard to image strong changes in spectral shape if protons diffuse from centre to us in 10 8 yr W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 28
Objections from astronomers Astronomers: outer rotation curve determined with different method than inner rotation curve. Hard to compare. Furthermore slope depends on distance to centre (R 0 ) v Sofue &Honma Inner rotation curve Outer rotation curve R 0 =8.3 kpc R 0 =7.0 Answer: First points of outer rot. curve in perfect agreement with inner rot. curve. CHANGE in slope for any R 0 R/R 0 Black hole at centre: R 0 =8.0±0.4 kpc W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 29
7 Physics Questions answered SIMULTANEOUSLY by this analysis 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 14 kpc? Why ring of molecular hydrogen at 4 kpc? 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: isothermal cored profile+substructure A: Cross sections perfectly consistent with msugra for light gauginos, heavy squarks/sleptons W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 30
Positrons Positron fraction and antiprotons from present balloon exp. Preliminary Antiprotons Signal Background Signal Background SAME Halo and WIMP parameters as for GAMMA RAYS but fluxes dependent on propagation! DMA can be used to tune models: at present no convection, nor anisotropic diffusion in spiral arms. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 31
What about Supersymmetry? W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 32
Allowed msugra region LHC: light gauginos easily observable A 0 =0 tb=50 What about WMAP? Not used sofar. Large tanβ 50->WMAP ok. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 33
10-27 Annihilation cross sections in m 0 -m 1/2 plane (µ > 0, A 0 =0) tan=5 tan=50 bb t t 10-24 bb t t EGRET WMAP ττ WW ττ WW For WMAP x-section of <σv> 2.10-26 cm 3 /s one needs large tanβ W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 34
Gauge unification perfect with SUSY spectrum from EGRET SM SUSY Update from Amaldi, db, Fürstenau, PLB 260 1991 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 W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 35
LSP = largely bino ( spin ½ photon) LSP largely Bino DM may be supersymmetric partner of CMB Charginos, neutralinos and gluinos light W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 36
Back to annihilation diagrams 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 B-Fragmentation known -> Spectra of Positrons, Gammas and Antiprotons known! Galaxy = Super B-Factory with rate 10 40 x B-Factory W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 37
Momentum dependence of contributions to DM annihilation Mχ 0 =50 GeV Mχ 0 =70 GeV decoupling time (250 ns after BB) If Z0 exchange dominates, then practically NO annihilation in present universe, since p 0 for CDM W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 38
EGRET data itself also implies large m0! SPA1a π 0 IC Brems WIMPS Gamma Spectra for different decay channels Gamma Spectra with tau-decays dominant (m 0 small) W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 39
Summary 10σ EGRET excess shows all key features from DM annihilation: Excess has same shape in all sky directions: everywhere it is perfectly (only?) explainable with superposition of background AND mono-energetic quarks of 50-100 GeV Results consistent with minimal SUPERSYMMETRY Excess follows expectations from galaxy formation: cored 1/r 2 profile with substructure, visible matter/dm 0.02 Excess is TRACER OF DM, since it can explain peculiar shape of rotation curve Significance >10σ with >1400 indep. data points Results rather model independent, since only KNOWN spectral shapes of signal and background used, NO model dependent calculations of abs.fluxes. Conventional models CANNOT explain above points SIMULTANEOUSLY, especially spectrum of gamma rays in all directions, 1/r 2 profile, shape of rotation curve, ring of stars at 14 kpc and ring of H 2 at 4 kpc,. W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 40
Summary of summary WIMP is thermal relic showing 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) Spatial distribution of annihilation signal is signature for DMA Different background shape yields same spatial distribution, which shows that gamma ray excess indeed traces DM W. de Boer, Univ. Karlsruhe Tübingen, Feb. 10, 2006 41