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On the origin of the WMAP Haze
Outline

• Synchrotron radiation in (new) Galactic Models
• Consistency with data from Integral, Egret,
  WMAP,
• Haslam, secondary CR production (like B/C),
• CR lifetimes (from cosmic clocks, like
  radioactive 10Be)

• What are signals of dark matter annihilation?
• Charged particles depend on propagation in
  Galaxy Gamma rays practically
  without absorption,
• so they point back to source

2
Trapping of CRs between MCs
MC have high magnetic fields (flux freezing
during contraction)
MC take only small fraction of volume of disk
(2)
Consequently field lines between them and MCs
line up like compass needle
Field in between MCs will act as magnetic trap
for CRs (e.g. van Allen) (when gyroradiusltlttrap
length)
Flux freezing in MC-gt reversing mag. fields
Trapping time regulates CRs lifetime and
secondary production
Indirect evidence for trapping from INTEGRAL it
explains why positrons annihilate only in warm
gas between MCs, not inside MCs or in hot gas
3
Indirect evidence for trapping from 511 keV
positron annihilation line (INTEGRAL)
Jean et al., astro-ph/0509298
NO annihilation in molecular clouds (MC) or hot
gas, ONLY in warm gas between MC (although 75 of
mass in MC) Why? MC are magnetic mirrors as
postulated by Chandran, 99
4
NATURE 452, 17. April 2008, Blown away by
cosmic rays, D.Breitschwerdt
Cosmic Rays (CR) form a plasma. If blowing in a
given direction, it will take other particles
with it, thus exerting pressure. This CR pressure
drives all halo particles to intergalactic
space, thus reducing strongly the flux of charged
particles from DMA.
Convection observed between 100 and 3000 km/s,
thus dominating over diffusion in the disk region
5
CR trapping between MC clouds?
It is shown that Galactic cosmic rays can be
effectively confined through magnetic reflection
by molecular clouds Chandran, 1999
Propagation slow in disk by trapping fast in
halo by convection
6
Diffusion vs Convection dominance
(Iris Gebauer, KA)
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Secondary production (B/C) and cosmic clocks
(10Be/9Be)
B/C determines grammage
10Be/9Be determines escape time
10Be (t1/2 1.51 Myr) is cosmic clock lifetime
of cosmics 107 yrs. In diffusion dom. by large
halo In convection dom. by slow propag
B/Csecondary/prim.determines grammage (smaller
than disk!) In diffusion dom. by large halo In
convection dom. by slow propagation in disk.
8
What is known about dark matter annihilation?

• Annihilation cross section known from
• Hubble expansion parameter
• (assuming WIMP thermal relic)
• DMA signature known from ee- annihilation
• Distribution of DM density ? 1/r2, so
• strongest towards center of Galaxy
• (for flat rotation curve)

9
Expansion rate of universe determines WIMP
annihilation cross section
Thermal equilibrium abundance
Actual abundance
Comoving number density
WMAP -gt ?h20.113?0.009 -gt
lt?vgt2.10-26 cm3/s
DM increases in Galaxies ?1 WIMP/coffee cup ?105
lt?gt. DMA (??2) restarts again..
Annihilation into lighter particles, like quarks
and leptons -gt ?0s -gt Gammas!
TM/22
10-9s
Only assumption in this analysis WIMP THERMAL
RELIC!
xm/T
Gary Steigmann/ Jungmann et al.
10
Example of DM annihilation (SUSY)
37 gammas
Quark fragmentation known! Hence spectra of
positrons, gammas and antiprotons known! Relative
amount of ?,antiprotons and e known as well.
Dominant ? ? ? A ? b bbar quark pair Sum of
diagrams should yield ltsvgt2.10-26 cm3/s to
get correct relic density
11
Constraints for indirect dark matter searches
From rotation curve Forces mv2/rGmM/r2 so
M/rconst. for vcons. and ??(M/r)/r2 , so
??1/r2 for flat rotation curve Divergent for
r0? Cuspy, cored? New N-body simulations Diffus
e component cuspy Clumpy component cored, see
Springel, Frenk, et al. arXiv0801.1127v1 Einasto
profile
R1
Sun
disc
R
IF FLUX AND SHAPE MEASURED IN ONE DIRECTION, THEN
FLUX ANDSHAPE FIXED IN ALL (180) SKY
DIRECTIONS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!
THIS IS AN INCREDIBLE CONSTRAINT, LIKE SAYING I
VERIFY THE EXCESS AND WIMP MASS WITH 180
INDEPENDENT MEAS.
12
Indirect Dark Matter Signals

• 511 keV emission from the galactic bulge
  (INTEGRAL)
• The HEAT positron excess
• EGRETs galactic gamma ray spectrum
• EGRETs extragalactic gamma ray spectrum
• The WMAP Haze

Dan Hooper SUSY07 Indirect Searches For
Particle Dark Matter
13
Background DMA describe EGRET data!
USE DATA DRIVEN CALIBRATION instead of relying on
background models or models for DM distribution
Fitted known shapes of background and DMA (from
accelerator experiments) with free
normalizations. W. de Boer et al., AA (2005)
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Analysis of EGRET data in 6 sky directions
C outer Galaxy
A inner Galaxy
B outer disc
Total ?2 for all regions 28/36 ? Prob. 0.8
Excess above background gtgt 10s.
E intermediate lat.
F galactic poles
D low latitude
A inner Galaxy (l300, blt50) B Galactic
plane avoiding A C Outer Galaxy
D low latitude (10-200) E intermediate lat.
(20-600) F Galactic poles (60-900)
15
Fits for 180 instead of 6 regions
180 regions 80 in longitude ? 45 bins 4 bins in
latitude ? 00ltblt50 50ltblt100
100ltblt200 200ltblt900 ? 4x45180 bins ?
gt1400 data points. Reduced ?21 with 7
errors BUT NEEDED IN ADDITION to 1/r2 profile,
substructure in the form of 2 doughnut-like rings
in the Galactic disc! ONE RING COINCIDES WITH
ORBIT FROM THE CANIS MAJOR DWARF GALAXY which
looses mass along orbit by tidal forces. Found by
EGRET and confirmed by gas flaring OTHER RING
coincides with H2 ring
16
Prediction of rotation curve from EGRET excess
Cored isothermal profile, as expected from
NFW authors, arXiv0801.1127
300 kpc
From distribution of DM one can calculate the
rotation curve. This works, thus directly
relating DM with the EGRET excess!
17
Comparing antiprotons in convection and
diffusion dominated propagation
Convection dominated
Diffusion dominated
Summary convection perpendicular to disk
reduces contribution of charged particles from
DMA by large factor and can be consistent with
B/C and 10Be/9Be
18
Electron spectrum can be tuned independently of
positrons by Galactic Magnetic Fields
(constrained by synchrotron maps)
Note propagation parameters do NOT cancel in
ratio e/(e e-), since e from p decays,
mainly produced locally by cosmic rays on gas of
disk, while e- from SN explosions, produced far
away!
19
THE EXTRAGALACTIC GAMMA RAY BACKGROUND
consistent with EGRET excess if DMA in foreground
taken into account
?2/d.o.f10.9/6 ? P0.1
D. Elssässer and K. Mannheim, Phys.Rev.Lett.9417
1302,2005
W.de Boer et al., AA, 2007 astro-ph/0705.009 Phys
.Rev. Lett..95209001,2005, DMA in foreground
taken into account
Problem large excess since they ignore DMA
signal in foreground
20
The WMAP Haze Spectrum and longitudinal
distribution
HASLAM 408 MHz
Haze Hooper, Dobler and Finkbeiner,
arXiv0705.3655
CR syn
Haze
WMAP Finkbeiner
EGRET DM
Arguments for Haze being DM signal steep
increase as expected for NFW profile (but not
supported by NFW anymore) DMA interpretation
excluded by upper limit from EGRET gamma rays
21
Uncertainties in interstellar electron spectrum

• Uncertainties in synchrotron spectrum
• Pressure from solar wind reduces flux of low
  energy particles
• (solar modulation).
• Effective in 1-10 GeV range, i.e. in WMAP
  frequency range!
• Fresh components and strongly localized
  B-fields can enhance
• locally the synchrotron radiation

22
Conclusion on EGRET excess
Excess shows text book signature of DMA

Excess observed in all sky directions
Excess has SAME spectral shape in all sky
directions corresponding to p0 spectrum from
mono-energetic quarks (as is known from ee-
annihilation at LEP accelerator)
Intensity of excess is distributed as expected
from gravitational potential, since rotation
curve can be reconstructed from it (i.e. direct
link between DM and excess)
Lets wait for GLAST and LHC if they confirm this
text book picture of DMA from the EGRET excess
with a 50-70 GeV WIMP.
23
Summary
Propagation models can describe spectral index of
synchrotron rad.

• Intriguing hint of trapping of CRs in between
  MCs from INTEGRAL
• (because no positron annihilation in MCs). This
  implies
• magnetic fields in MCs larger than turbulent
  field,
• (large fraction of CRs in traps (from fit and
  predicted by Zirakashvili, 2001)
• and field lines between MCs will tend to
  alternate field between spiral arms)
• Propagation models based on trapped CRs explain
  many features
• (compatible with observed large convection and
  slow diffusion in disk, lifetime of CRs,
  grammage, small radial gradient of gamma rays,
  DMA interpretation of EGRET excess without too
  many antiprotons, large bulge/disk ratio of
  INTEGRAL 511 keV line)

EGRET data set upper limit of few on DMA
contribution to synchrotron spectra, so WMAP Haze
not from DMA
24
Do Galactic Foregrounds need MC traps?
In review talk by Bryan Gaensler on synchrotron
radiation Galactic 3D-emission models, Sun et
al. arXiv0711.1572 Abstract From a comparison
of simulated and observed maps we are able to
constrain the regular large-scale Galactic
magnetic field in the disk and the halo of the
Galaxy.
Conclusion to get a good chi2 they introduce a
coupling factor, since the thermal electron
density and the magnetic field strength are
correlated. However, we note that the physics and
a theoretical value for the coupling factor needs
to be worked out.
INTEGRAL data explained as trapping provides this
theory for free!!