Gary Hinshaw NASA/GSFC
From Quantum to Cosmos, Airlie Center VA, July 8 2008
5-year Results from WMAP5-year Results from WMAP with a Glimpse Ahead with a Glimpse Ahead
WMAP MissionWMAP Mission
WMAP’S PURPOSE –
To make a detailed full-sky map of the CMB radiation anisotropy (temperature and polarization) to constrain the cosmology of our universe.
W = WilkinsonW = Wilkinson
WMAP Science TeamWMAP Science Team
WMAP’s Differential Receivers*WMAP’s Differential Receivers*
10 “Differencing Assemblies”
4 @ 94 GHz W-band
2 @ 61 GHz V-band
2 @ 41 GHz Q-band
1 @ 33 GHz Ka-band
1 @ 23 GHz K-band
*based on HEMT design of M. Pospieszalski
WMAP LaunchWMAP Launch
June 30, 2001 at 3:47 EDT
Delta II Model 7425-10Delta Launch Number 286 Star-48 third stage motor Cape Canaveral Air Force StationPad SLC-17B
WMAP at L2WMAP at L2
WMAP at L2WMAP at L2
Taken with ESO 2.2 m telescope, La Silla Chile, for GAIA optical tracking test.
3 images (R,G.B) taken a few minutes apart, V=19.4.
WMAP Sky CoverageWMAP Sky Coverage
Not to scale:Earth — L2 distance is 1% of Sun — Earth Distance
Earth
Sun
MAP at L2
1 Day
3 Months
6 Months - full sky coverage
129 sec. (0.464rpm) Spin
22.5° half-angle1 hour precession cone
A-side line of site
B-side line of site
MAP990159
5-year Temperature Maps5-year Temperature Maps
5-year Polarization Maps5-year Polarization Maps
5-year Absolute Calibration5-year Absolute Calibration
New dipole fitting technique yields absolute gain accuracy of New dipole fitting technique yields absolute gain accuracy of <0.2% (difference between red and black curves).<0.2% (difference between red and black curves).
5-year Beam Calibration5-year Beam Calibration
Major effort to model beam response down to -44 dB allows us to model Major effort to model beam response down to -44 dB allows us to model PSF response with factor of ~2 improvement in accuracy. (Hill et al.)PSF response with factor of ~2 improvement in accuracy. (Hill et al.)
Jupiter data Physical model ResidualJupiter data Physical model Residual
A sideA side
B sideB side
3-year Power Spectrum - TT3-year Power Spectrum - TT
5-year Power Spectrum - TT5-year Power Spectrum - TT
Important DatesImportant Dates
Inflation – initial conditions: A, r, ns
Dark ages → first stars – polarization: τ
Plasma epoch – matter, radiation content: Ωb, Ωc
Large scale structure – dark energy: ΩΛ, σ8
5-year 5-year ΛΛCDM ParametersCDM Parameters
Blue curves/contours – 5-year data
Grey curves/contours – 3-year data
Biggest improvements in:
Optical depth, τ
Amplitude of fluctuations @ 8 Mpc, σ8
Matter densities, Ωbh2, Ωch2
TE EE
Was reionization a complex process?
Low-l TE and EE polarization power spectra can distinguish between different ionization histories.
Plots show mean TE, EE spectra for range of reionization histories.
Reionization - IReionization - I
Reionization - IIReionization - II
Improved polarization data improves measurement of optical depth and/or reionization redshift. Also begin to probe 2nd reionization parameter.
The bulk of the reionization had to occur at z>6, thus it had to be an extended process.
Cosmic Neutrino BackgroundCosmic Neutrino Background
Evidence for the cosmic neutrino background, “would provide the most dramatic possible confirmation of the standard model of the early universe”
The First Three Minutes Steven Weinberg 1977On seeing evidence for the cosmic neutrino background
New limits on gravitational wave amplitude, r<0.2.
Information still largely comes from shape of TT spectrum.
Testing Inflation - ITesting Inflation - I
“Named” inflation models are currently being put to the test.
Many of the models predict an observable gravitational wave background (via the CMB B-mode polarization).
Testing Inflation - IITesting Inflation - II
Future WMAP OperationsFuture WMAP Operations
WMAP is nearing 7 years at L2 and has been approved for 2 final years of operation.
What important questions will more WMAP data help address?
• Reionization - was reionization an extended process? Was the universe partially reionized at z = 20 or 30?
• Dark Energy - upcoming dark energy experiments will be limited by WMAP cosmological parameter uncertainties. Additional WMAP data will improve these uncertainties.
• Physics of Inflation - primordial gravity waves, primordial non-Gaussianity, deviations from scale invariance.
• Also: polarized synchrotron data, radio source & planet data, calibration source for ground/balloon-based experiments
4/24/2008 WMAP 2008 Senior Review 23
Output counts per unit of input temperature difference changes with time due to changes in spacecraft temperature and amplifier properties.
Multiple years of data help to separate these effects and improve uncertainty in the gain model.
Change in instrument offset vs. time. Additional years of data improve our knowledge of the sources of offset: thermal emission, gain variation, etc.
Detailed Understanding of InstrumentDetailed Understanding of Instrument
TT 5-Yr
TT 9-Yr
TE 5-Yr
TE 9-Yr
EE
Dark EnergyDark Energy
WMAP5 and the Cluster Mass FunctionK. Rines, A. Diaferio & P. Natarajan
arXiv:0803.1843
Growth FunctionCombined LSS and CMB measurements probe Dark Energy. Improvements in cluster counts (Chandra, ROSAT, SDSS, DES, Pan-STARRS, etc.) and weak lensing surveys will demand better measurements of 8 and m to constrain w(z).
The predicted number of massive clusters (alternatively, the SZ power spectrum) scales as 8
7 !
Acoustic scale WMAP measures the sound horizon at z=1090. This acoustic scale is the fundamental calibration for on-going and planned baryon acoustic oscillation measurements.
lA = 302.08 ± 0.84 (5 yr) → ± 0.64 (9 yr)(30% improvement)
Closing in on Closing in on 88 and and mm
2006
2006
2006
Chandra cluster counts: Vikhlinin et al.Chandra cluster counts: Vikhlinin et al.
2008+
InflationInflation
• Have we detected deviations from scale-invariance?
~2.5 σ
• Is there a running spectral index?
Probably not.
• Is there primordial non-Gaussianity?
Not yet…
• What is the amplitude of tensor modes (gravitational waves)?
r<0.2
Testing InflationTesting Inflation
Future CMB From SpaceFuture CMB From Space• Planck
Spacecraft is integrated, launch is imminent! See next talk.
• CMBPol
High sensitivity polarization to probe gravity waves from Inflation.
Inflation and Gravity Waves - IInflation and Gravity Waves - I• Inflation predicts two forms of fluctuations:
– Scalar modes (density perturbations) with slope ns:
• generate CMB anisotropy and lead to structure formation
– Tensor modes (gravity waves) with slope nt:
• generate CMB anisotropy but do not contribute to structure formation• Gravity wave amplitude, r, proportional to energy scale of inflation:
• Both types of fluctuations contribute to CMB temperature anisotropy:
scalar
tensor
pl kP
kPr
E
mr
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GeV103.3
V
0
016
infl
1/44/1
Inflation and Gravity Waves – IIInflation and Gravity Waves – II• Both types of fluctuations contribute to CMB polarization anisotropy:
– Scalar modes produce only “E-mode” polarization patterns, by symmetry– Tensor modes produce both “E-mode” and “B-mode” polarization patterns (see
below)• The observation of B-mode polarization uniquely separates scalar and tensor modes
from inflation and measures the energy scale of inflation.• Only known probe of physics at E ~ 1016 GeV… 12 orders of magnitude higher than
planned accelerators.
E – scalar+tensor B – tensor only
Sensitivity & Foreground EstimatesSensitivity & Foreground Estimates
Blue band -Galactic foreground estimate from WMAP3, frequency dependent
Green line -Lensing (EE→BB), frequency independent
Red lines -Gravity wave signal(s)
Grey shaded band - 1-sigma sensitivity for 1000-channel system with 1-yr integration, 1°FWHM resolution
r=0.01
r=0.3
Candidate CMBPol ConceptCandidate CMBPol Concept
Multiple copies of basic polarimeter module, scaled in frequency, packaged in focal plane, co-aligned along s/c symmetry axis.
4/24/2008 WMAP 2008 Senior Review 38
Monodromy in the CMB: Gravity Waves and String InflationEva Silverstein and Alexander Westphal
http://arxiv.org/abs/0803.3085v2
Large-field inflation (hence gravitational waves) from string theory compactified on twisted tori.