09.08.2015 Views

Ingredients to this analysis

The dark connection between Canis Major, Monoceros Stream, gas ...

The dark connection between Canis Major, Monoceros Stream, gas ...

SHOW MORE
SHOW LESS
  • No tags were found...

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

The dark connection between Canis Major, Monoceros Stream,gas flaring, the rotation curve and the EGRET excessFrom EGRET excess of diffuseGalactic gamma rays• Determination of WIMP mass• Determination of WIMP halo(= standard halo + DM ring)Confirmation of DM ring:• Rotation curve• N-body similation ofCanis Major/Monoceros stream• Gas flaringPREDICTIONS• for LHC (if SUSY)• for direct searches• for solar neutrinos<strong>Ingredients</strong><strong>to</strong> <strong>this</strong> <strong>analysis</strong>AstronomersAstrophysicsCosmologyParticle PhysicsRotation curveDoughnut of starsat 13 kpcDoughnut of H 2at 4 kpcGas flaringCosmicsGamma rays23%DM, thermalhis<strong>to</strong>ry of WIMPsannihilationcross sectionGalaxy formationgamma spectrafor BG + DMASUSYWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 1


What is known about Dark Matter?• 95% of the energy of the Universe isnon-baryonic23% in the form of Cold Dark MatterFrom CMB + SN1a + surveys• Dark Matter enhanced in Galaxies and Clustersof Galaxies but DM widely distributed in halo->DM must consist of weakly interacting andmassive particles -> WIMP’sIf it is not darkIt does not matter• Annihilation with =2.10 -26 cm 3 /s,if thermal relicDM halo profile of galaxycluster from weak lensingWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 2


Thermal His<strong>to</strong>ry of WIMPsThermal equilibrium abundanceActual abundanceComoving number densityT=M/22x=m/TJungmann,Kamionkowski, Griest, PR 1995T>>M: f+f->M+M; M+M->f+fTf+fT=M/22: M decoupled, stable density(when annihilation rate ≅ expansionrate,i.e. Γ=nχ(x fr ) ≅ H(x fr ) !)WMAP -> Ωh 2 =0.113±0.009 ->=2.10 -26 cm 3 /sDM increases in Galaxies:≈1 WIMP/coffee cup ≈10 5 .DMA (∝ρ 2 ) restarts again..Annihilation in<strong>to</strong> lighter particles, likequarks and lep<strong>to</strong>ns -> π 0’s -> Gammas!Only assumption in <strong>this</strong> <strong>analysis</strong>:WIMP = THERMAL RELIC!Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 3


How do particles annihilate?e+e-LEP collider:e+e- annihilation~~qqpho<strong>to</strong>n annihilationγγ~~~~eeeIn CM: Eq=Eemonoenergetic quarksfrom monoenergetic lep<strong>to</strong>nsQuarks fragment in<strong>to</strong> jets,mostly light mesons:π+,π-,π0π0 decays 100% in<strong>to</strong> 2 pho<strong>to</strong>nsSo as many pho<strong>to</strong>ns as charged particlesfrom annihilationOn averaged: 37 pho<strong>to</strong>ns pro annihilationin<strong>to</strong> quarks at LEPSpectral shape VERY WELL MEASUREDWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 4


Example of DM annihilation (SUSY)χχ~fffχχAffχχZffχχχWχ ± χ 0WχZZ≈37gammasDominantχ + χ ⇒A ⇒ b bbar quark pairSum of diagrams should yield=2.10 -26 cm 3 /s <strong>to</strong> getcorrect relic densityQuark-Fragmentation known!Hence spectra of positrons,gammas and antipro<strong>to</strong>ns known!Relative amount of γ,p,e+ knownas well.Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 5


Conclusion sofarIF DM particles are thermal relics from early universethey MUST annihilate with cross section=2.10 -26 cm 3 /swhich implies enormous rate of gamma raysfrom π 0 decays (produced in quark fragmentation)(Galaxy=10 40 higher rate than any accelera<strong>to</strong>r)Expect large fraction of energetic Galactic gamma rays<strong>to</strong> come from DMARemaining ones from p CR +p GAS -> π 0 +X , π 0 ->2γThis means: Galactic gamma rays have 2 componentswith a shape KNOWN from the 2 BEST studied reactionsin accelera<strong>to</strong>rs: background known from fixed target exp.DMA known from e+e- annihilation (LEP)Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 6


EGRET on CGRO (Comp<strong>to</strong>n Gamma Ray Observ.)Data publicly available from NASA archiveInstrumental parameters:Energy range: 0.02-30 GeVEnergy resolution: ~20%Effective area: 1500 cm 2Angular resol.:


Energy loss times of electrons and nucleiτ -1 = 1/E dE/dtτ univPro<strong>to</strong>ns diffuse much faster than energy loss time, soexpect SAME shape everywhere. Indeed observed: outerGalaxy can be fitted with same shape as inner Galaxy.Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 8


What about background shape?No SMNo SMQuarksfromWIMPSPro<strong>to</strong>nsElectronsQuarksin pro<strong>to</strong>nsBackground from nuclear interactions (mainly p+p-> π 0 + X -> γ + Xinverse Comp<strong>to</strong>n scattering (e-+ γ -> e- + γ)Bremsstrahlung (e- + N -> e- + γ + N)Shape of background KNOWN if Cosmic Ray spectra of p and e- knownWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 9


PYTHIA processes:Contribution from various hadronic processes11 f+f' -> f+f' (QCD) 237012 f+fbar -> f'+fbar' 013 f+fbar -> g + g 028 f+g -> f + g 213068 g+g -> g + g 151053 g+g -> f + fbar 2092 Single diffractive (XB) 167093 Single diffractive (AX) 160094 Double diffractive 70095 Low-pT scattering 0Prompt pho<strong>to</strong>n production:14 f+fbar -> g+γ 018 f+fbar -> γ +γ 029 f+g -> f +γ 1115 g+g -> g + γ 0114 g+g -> γ + γ 02 GeV48163264diff.Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 10


Basic principle for indirect dark matter searchesFrom rotation curve:mv 2 /r=GmM/r 2 =cons.andρ∝(M/r)/r 2ρ∝1/r 2for const. rot.curveSunSunR 1RbulgediscdiscEXPECT MOST OF DMIN CENTRE OF GALAXYRDivergent for r=0?NFW profile∝1/rIsotherm profile const.IF FLUX AND SHAPE MEASURED INONE DIRECTION, THEN FLUX ANDSHAPE FIXED IN ALL (=180) SKYDIRECTIONS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!THIS IS AN INCREDIBLE CONSTRAINT, LIKE SAYING I VERIFYTHE EXCESS AND WIMP MASS WITH 180 INDEPENDENT MEAS.Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 11


Background + signal describe EGRET data!WdB, C. Sander, V. Zhukov, A. Gladyshev, D. Kazakov,EGRET excess of diffuse Galactic Gamma Rays asBackground Tracer of DM, + astro-ph/0508617, DMA signal A&A, describe 444 (2005) EGRET 51 data!50 GeVICπ 0 WIMPSπ 0ICWIMPSBrems.IC70Brems.Blue: background uncertaintyBlue: WIMP mass uncertaintyWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 12


Analysis of EGRET data in 6 sky directionsA: inner GalaxyB: outer discC: outer GalaxyTotal χ 2 for all regions :28/36 ⇒ Prob.= 0.8 Excess above background > 10σ.D: low latitude E: intermediate lat. F: galactic polesA: inner Galaxy (l=±30 0 , |b|


Fits for 180 instead of 6 regions180 regions:8 0 in longitude ⇒ 45 bins4 bins in latitude ⇒ 0 0


Background scaling fac<strong>to</strong>rs agree withexpectations of gas- and CR densitiesBackground scaling fac<strong>to</strong>r = Data between 0.1 and 0.5 GeV/GALPROPGALPROP = computer code simulating our galaxy (Moskalenko, Strong)Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 15


Dark Matter distributionxyxzExpectedProfilev 2 ∝M/r=cons.andρ∝(M/r)/r 2ρ∝1/r 2for const.xzrotationcurveDivergent forr=0?NFW∝1/rIsotherm const.Halo profileObservedProfilexyRotation Curvexy2002,Newberg et al. Ibata et al,Crane et al. Yanny et al.diskRbulgeWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 16zInner Ring<strong>to</strong>talDM1/r 2 haloOuter Ring1/r 2 profile and ringsdetermined from independentdirectionsNormalize <strong>to</strong> solar velocity of 220 km/s


N-body simulations show: Progeni<strong>to</strong>r of 13 kpc ring= Canis Major Dwarf just below Galactic discWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 17


N-body simulation from Canis-Major dwarf galaxyObserved starsR=13 kpcprogradeCanis Major (b=-15 0 )retrogradePenarrubia et al.astro-ph/0410448astro-ph/0703601Predicted DM ring from N-bodysimulations, relying only on stars,COINCIDED PERFECTLYwith EGRET excess:•radius of ring 13 kpc•ellipticity = 0.95•angle of major axis -20 0•Retrograde orbit excludedWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 18


Excess of DM from Canis Major +tidal stream indeed seenDark matter signal (arb. units)latitudelatitudeCMWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 19


Gas flaring in the Milky WayKalberla (Univ. Bonn):If one includes ring of DMwith mass 2.10 10 M sunflaring perfectly unders<strong>to</strong>odno ringwith ringWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 20


Inner Ring coincides with ring of dust and H 2 ->gravitational potential well!H 2Enhancement of inner (outer) ringover 1/r 2 profile 6 (8).Mass in rings 0.3 (3)% of <strong>to</strong>tal DM4 kpc coincides with ring ofneutral hydrogen molecules!H+H->H 2in presence of dust->grav. potential well at 4-5 kpc.Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 21


Does antipro<strong>to</strong>n data exclude interpretation of EGRET data?Bergstrom et al. astro-ph/0603632, Abstract:we investigate the viability of the model using the DarkSUSYpackage <strong>to</strong> compute the gamma-ray and antipro<strong>to</strong>n fluxes. We areable <strong>to</strong> show that their (=WdB et al) model is excluded by a widemargin from the measured flux of antipro<strong>to</strong>ns.Problem with DarkSUSY (DS):1) Flux of antipro<strong>to</strong>ns/gamma in DarkSUSY: O(1) from DMA.However, O(10 -2 ) from LEP dataReason: DS has diffusion box with isotropic diffusion ->DMA fills up box with high density of antipro<strong>to</strong>ns2) More realistic models have anisotropic diffusion.E.g. spiral galaxies have magnetic fields perpendicular <strong>to</strong>disk-> antipro<strong>to</strong>ns may spiral quickly out of Galaxy.In addition: convection of particles by CR pressure.Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 22


Magnetic fields observed in spiral galaxiesfieldlinediskA few uG perpendicular <strong>to</strong> disc:Strong convection ⊥ <strong>to</strong> disc?A few µG along spiral arms:Can lead <strong>to</strong> slow radial diffusionIsotropic diffusion assumes randomly oriented magnetic turbulences.Preferred magnetic field directions -> anisotropic diffusionWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 23


Preliminary results from GALPROPwith isotropic and anisotropic propagationAntipro<strong>to</strong>nsB/C ratioSummary: with anisotropic propagation you can send charged particleswhereever you want and still be consistent with B/C and 10 Be/ 9 BeWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 24


What about supersymmetry?Present data does not say anything on SUSY.But only consistent with SUSY ifGAUGINOS LIGHT (


Annihilation cross sectionsin m 0 -m 1/2 plane (μ > 0, A 0 =0)Annihilation cross sections canbe calculated,if masses areknown (couplings as in SM).Assume not only gauge couplingunification at GUT scale, butalso mass unification, i.e. allspin 0 (spin 1/2) particles havemasses m0 (m1/2).For WMAP x-section of≅2.10 -26 cm 3 /s one needsfor small LSP mass (m1/2 ≈ 175GeV) large values of (m0 ≈ 1-2Tev) (and large tan β ≈50)10 -24 EGRETWMAPbbττt tWWmSUGRA: common masses m0 and m1/2 for spin 0 and spin ½ particlesWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 26


Expected SUSY mass spectra in mSUGRAmSUGRA: common masses m 0 and m 1/2 for spin 0 and spin ½ particlesWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 27


Gauge unification perfect with SUSY spectrum from EGRETSMSUSYUpdate from Amaldi, dB,Fürstenau, PLB 260 1991NO FREEPARAMETERWith SUSY spectrum from EGRET + WMAP data and start valuesof couplings from final LEP data perfect gauge coupling unification!Also b->sγ and g-2 agree within 2σ with SUSY spectrum from EGRETWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 28


Direct Detection of WIMPsWIMPs elastically scatter off nuclei => nuclear recoilsMeasure recoil energy spectrum in targetSpin dependent and indep.χ 0 χ 0Spin independent ∝Number of nuclei 2(coherent scattering on all nuclei!)Spin dependentWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 29


Cross sections for Direct DM detection in mSUGRAEGRET?Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 30


DM annihilation in Sun and EarthSUNEARTHEGRETEGRETWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 31


Summary>10σ EGRET excess shows thatWIMP is thermal relic with expected annihilation in<strong>to</strong> quark pairsDM 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 ofsignal and background used, NO model dependent calculations of abs.fluxes.Different models or unknown experimental problems may change boostfac<strong>to</strong>r and/or WIMP mass, BUT NOT the distribution in the sky.SPATIAL DISTRIBUTION of annihilation signal is signature for DMAwhich clearly shows that EGRET excess is tracer of DM by fact tha<strong>to</strong>ne can CONSTRUCT ROTATION CURVE FROM GAMMA RAYS.DM interpretation strongly supported N-body simulation of CanisMajor dwarf and its tidal streams coinciding with the EGRET excessEGRET shows lots of DM mass in the tidal streams -> GAS FLARINGWim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 32


Summary on WIMP searchesIndirect detection: (SPACE EXPERIMENTS)intriguing hint for signals from DMA for60 GeV WIMP from gamma raysDirect detection: (UNDERGROUND OBSERVATORIES)expected <strong>to</strong> observe signal in near futureIF we are not in VOID of clumpy DM haloDirect production:(ACCELERATORS (LHC 2008-2018)):cannot produce WIMPs directly(<strong>to</strong>o small cross section), BUT IF WIMPsare Lightest Supersymmetric Particle (LSP) THENWIMPs observable in DECAY of SUSY particlesIF EVERY METHOD measures SAME WIMP mass, then PERFECT.In <strong>this</strong> case Dark Matter is the supersymmetric partner of the CMB!Wim de Boer, Karlsruhe Seminar Oxford, May. 3, 2007 33

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!