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Gravitationslinsen Rotationskurven Indirekter Nachweis der DM

Nachweismethoden der DM. Gravitationslinsen Rotationskurven Indirekter Nachweis der DM ( Annihilation der DM in Materie-Antimaterie) Direkter Nachweis der DM ( Elastische Streuung an Kernen). Gravitationslinsen. ART: Die Ausbreitung von Licht ändert sich

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Gravitationslinsen Rotationskurven Indirekter Nachweis der DM

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  1. Nachweismethoden der DM Gravitationslinsen Rotationskurven Indirekter Nachweis der DM ( Annihilation der DM in Materie-Antimaterie) Direkter Nachweis der DM ( Elastische Streuung an Kernen)

  2. Gravitationslinsen ART: Die Ausbreitung von Licht ändert sich beim Durchgang durch ein Gravitationsfeld

  3. Gravitationslinsen

  4. Colliding Clusters Shed Light on Dark Matter Blau: dunkle Materie aus Gravitations- potential dunkel Rot: sichtbares Gas • Observations with bullet cluster: • Chandra X-ray telescope shows distribution of hot gas • Hubble Space Telescope and others show distribution of dark matter • from weak gravitational lensing • Distributions are clearly different after collision-> • dark matter is weakly interacting!

  5. Simulation der “Colliding Clusters” http://www.sciam.com/ August 22, 2006

  6. Discovery of DM in 1933 Zwicky, Fritz (1898-1974 Zwicky notes in 1933 that outlying galaxies in Coma cluster moving much faster than mass calculated for the visible galaxies would indicate DM attracts galaxies with more force-> higher speed. But still bound!

  7. Dunkle Materie im Universum Die Rotationskurven von Spiralgalaxien sind weitgehend flach, während die leuchtende Materie eine abfallende Kurve erwarten lässt. Erklärung: dunkle Materie. Spiralgalaxien bestehen aus einem zentralen Klumpen und einer sehr dünnen Scheibe leuchtender Materie, welche von einem nahezu sphährischen, sehr ausgedehnten Halo umgeben ist.

  8. v=ωr Milchstraße Norma mv2/r=GmM/r2 Scutum Crux Perseus Sagittarius v1/r Orion Sun(8 kpc from center) Cygnus Messung der Masse durch Newtons Gravitationsgesetz

  9. Do we have Dark Matter in our Galaxy? Rotationcurve Solarsystem rotation curve Milky Way 1/r

  10. Estimate of DM density DM density falls off like 1/r2 for v=const. Averaged DM density “1 WIMP/coffee cup” (for 100 GeV WIMP)

  11. Für Ensemble wechselwirkender Systeme im mechanischen Gleichgewicht gilt Für N Teilchen, also N(N-1)/2 TeilchenpaarenFür N groß: und Virialsatz Erwarte also für ´Gas` gravitativ wechselwirkender Teilchen M  r ! Aber dann: vrot2M/r = konst -> flache Rotationskurve

  12. 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  Expansions- rate,i.e. =<v>n(xfr)  H(xfr) !) Expansion rate of universe determines WIMP annihilation cross section 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 10-9s Only assumption in this analysis: WIMP = THERMAL RELIC! x=m/T Gary Steigmann/ Jungmann et al.

  13. What is known about Dark Matter? • 95% of the energy of the Universe is • non-baryonic • 23% in the form of Cold Dark Matter • 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 • Annihilation with <σv>=2.10-26 cm3/s, • if thermal relic From CMB + SN1a + surveys If it is not dark It does not matter DM halo profile of galaxy cluster from weak lensing

  14. Kandidaten der DM † ? † ? Problem: max. 4% der Gesamtenergie des Univ. in Baryonen nach CMB und BBN. Sichtbar nur 0.5%, d.h. 3.5% in obigen Kandidaten möglich. Rest der DM muss aus nicht-baryonischen Materie bestehen. • Probleme: • ν< 0.7% aus WMAP Daten kombiniert mit Dichtekorrelationen der Galaxien. • Für kosmische Strings keine Vorhersagekraft. • Abweichungen von Newtons Gravitationsgesetz nicht plausibel. • WIMPS ergeben nach Virialtheorem flache Rotationskurven. • In Supersymmetrie sind die WIMPS • Supersymmetrische Partner der CMB • d.h. Spin ½ Photonen (Photinos genannt).

  15. Simple 3-Component Galaxy: p+e+Wimps Interactions: p+e <->H electromagnetic x-section p+p -> X strong x-section: 10-25 cm2 p+W -> p+W x-section:<10-43 cm2 (direct DM searches) W+W -> X x-section: 10-33 cm2 (Hubble expansion) These cross sections are exactly order of magnitude predicted by SUSY!

  16.   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

  17. Indirect Dark Matter Searches in the Light of ATIC, FERMI, EGRET and PAMELA Annihilation products from dark matter annihilation: Gamma rays (EGRET, FERMI) Positrons(PAMELA) Antiprotons(PAMELA) e+ + e- (ATIC, FERMI, HESS, PAMELA) Neutrinos (Icecube, no results yet) e-, p drown in cosmic rays?

  18. 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 significant fraction of energetic Galactic gamma rays to come from DMA in this case. Remaining ones from pCR+pGAS-> π0+X, π0->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)

  19. Anmerkungen zur indirekten Suche nach DM • Gamma rays: • keine Ablenkung durch das Galaktische Magnetfeld • zeigen daher in Richtung der Quelle • kaum Abschwächung in der Galaxie bei GeV Photonen • Astrophysikalische Quellen als Punktquellen erkennbar • und können daher subtrahiert werden • Untergrund hat anderes (aber bekanntes) Spektrum als DMA Signal. • Durch gleichzeitiges Fitten von Form des Spektrums für • Signal und Untergrund können beide Beiträge direkt aus den • Daten bestimmt werden, wenn man die Normierung als freier • Fitparameter behandelt (data driven analysis) • Geladene Teilchen: • Ablenkung durch das Galaktische Magnetfeld, sie zeigen daher • nicht in Richtung der Quelle • Wahrscheinlichkeit, dass z.B. Antiproton aus DMA im Detektor • ankommt, stark abhängig vom Propagationsmodell • Keine Trennung von astrophysikalischen Punktquellen möglich

  20. Quarks from WIMPS Quarks in protons Woher erwartet man Untergrund? Background from nuclear interactions (mainly p+p-> π0 + X ->  + X inverse Compton scattering (e-+  -> e- + ) Bremsstrahlung (e- + N -> e- +  + N) Shape of background KNOWN if Cosmic Ray spectra of p and e- known

  21. Energy loss times of electrons and nuclei t-1 = 1/E dE/dt univ Protons diffuse for long times without loosing energy! If centre would have harder spectrum, then hard to explain why excess in outer galaxy has SAME shape (can be fitted with same WIMP mass!)

  22. Usual astrophysicist’s search strategies Particle physicist: get rid of model dependence by DATA DRIVEN calibration

  23. 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

  24. Two results from EGRET paper Called “Cosmic enhancement Factor” Excess Enhancement in ringlike structure at 13-16 kpc 1 10 EγGeV

  25. Untergrund + DM Annihilation beschreiben Daten W. de Boer et al., 2005

  26. Analyse der EGRET Daten in 6 Himmelsrichtungen 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)

  27. Rotation Curve totalDM 1/r2 halo disk Sofue &Honma R0=8.3 kpc bulge v Inner rotation curve R0=7.0 Inner Ring Outer RC Outer Ring Black hole at centre: R0=8.00.4 kpc R/R0 Normalize to solar velocity of 220 km/s EGRET Excess predicts shape of rotation curve! Note 1: Absolute value of rotation curve depends on distances. But chance of slope can ONLY be explained by ringlike structure. Note 2: fact that shape of DM halo can describe shape of RC implies that EGRET excess has exactly right intensity to deliver grav. potential!

  28. 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 with mass of 2.1010M☉!

  29. 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

  30. e– e+ FERMI measures GeV gamma rays + electrons

  31. Diffuse gamma rays from FERMI 20% EGRET 100% Published FERMI data on VELA pulsar: agrees within errors with EGRET at 3 GEV astro-ph/0812.2960 Why diffuse spectrum disagrees 100% with EGRET at 3 GeV while VELA spectrum agrees with EGRET at 3 GeV within 20%?

  32. Indirect Dark Matter Searches using charged particles Annihilation products from dark matter annihilation: Gamma rays (EGRET, FERMI) Positrons(PAMELA) Antiprotons(PAMELA) e+ + e- (ATIC, FERMI, HESS, PAMELA) Neutrinos (Icecube, no results yet) e-, p drown in cosmic rays?

  33. The PAMELA Satellite Experiment (launched July 2006) Resurs Dk1 Satellite Transition Radiation Detector (removed for tech.reasons) 20.5 cm2sr ~10 T Anticoincidence Shield 1.2 m Silicon Tracker and Permanent Magnet Time of Flight Counters Si-W Electromagnetic Calorimeter Bottom Scintillator 300 - 600 km Neutron Detector ~450 kg

  34. PAMELA, positron and antiproton measurements Positron fraction Antiproton/proton ratio (O. Adriani et. al., PRL (2009)[0810.4994]) Nature 458:60,2009,arXiv:0810.4995 +prelim. new data, Boezio, Pamela-WS 2009 Pamela Galprop Antiprotons: NO excess Positrons: excess

  35. ATIC Balloon experiment, Nature 2008 Kaluza-Klein DM decaysto leptonpairs ->peak in electron spectrumwithtailfromenergylosses KK x-section Y4 so mainlydecayto leptonsand u-quarks Baltz, Hooper, hep-ph/0411053 Hooper, Zurek, 0902.0593

  36. Alexander Moiseev Pamela workshop May 11, 2009 FERMI electron spectrum: NO BUMP at 600 GeV Simulating the LAT response to a spectrum with an “ATIC-like” feature: This demonstrates that the Fermi LAT would have been able to reveal “ATIC-like” spectral feature with high confidence if it were there. Energy resolution is not an issue with such a wide feature

  37. Cherenkov telescopes measure TeV gamma rays HESS MAGIC

  38. HESS, May 2009 Electron spectrum falls off above 1 TeV

  39. Interpretations for charged particle anomalies • Many possibilities: • Background from hadronic showers • with large electromagnetic component -> ap->0 • astrophysical sources • pulsars -> apulsar • positron acceleration in SNR -> asec • locality of sources-> aSNR • dark matter annihilation-> aDMA • leptophilic? • bound states? • Kaluza-Klein

  40. Truth? Depends on whom you ask! My assumption: |Data>= ap->0 |Background> + aDMA |DMA> + asec |SNR> + alocal |SNR(x)> + apulsar |Pulsar> Unitarity must be fulfilled. However, will now show that each component has enough uncertainty to saturate observations

  41. aDMA:DM interpretation of FERMI e-data TeV DM decayingtolowscale particle, whichcanonly decayleptonically TeV DM formsboundstate toget large boostfactor via Sommerfeld enhancement Models e.g. by Arkani-Hamed,Finkbeiner,Slatyer,Weiner arXiv:0810.0713 Nomura and Thaler, arXiv:0810.5397 Fit by Bergstrom et al.arXiv:0905.0333

  42. aloc :3-component e- sources: spiral arm, disc, local Shaviv et al., arXiv:0902.0376,2009 nearsources disc spiral arm positrons e loose energy rapidly (dE/dt  E2), hence they are “local” 3-component structure explains e-spectrum, Pamela/Fermi anomalies andwhynothing in pbar Itcanwork!

  43. What about Supersymmetry? Assume mSUGRA 5 parameters: m0, m1/2, tanb, A, sign μ

  44.   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

  45. Expected SUSY mass spectra in mSUGRA for EGRET WIMP mass of 60 GeV mSUGRA: common masses m0 and m1/2 for spin 0 and spin ½ particles

  46. t t t t bb bb Annihilation cross sectionsin m0-m1/2 plane (μ > 0, A0=0) tan=5 tan=50 10-24 10-27 EGRET WMAP   WW WW For WMAP x-section of <v>2.10-26 cm3/s one needs large tanβ

  47. Mt/Mb = tan  Mb2=(4)2Yb v12 Mt2=(4)2Yt v22

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