Krzysztof M. Górski Jet Propulsion Laboratory/Caltech (Warsaw University Observatory)

Zeldovich 90 • Moscow, 20-24 Dec. 2004

Krzysztof M. Górski

Jet Propulsion Laboratory/Caltech

(Warsaw University Observatory)

Exploiting the CMB Observations from Space - Looking Forward to Planck and Beyond

Zeldovich 90 • Moscow, 20-24 Dec. 2004K.M. Gorski - 2

Another look at comparison to COBE-DMRAnother look at comparison to COBE-DMR


V-Band WMAP dataV-Band WMAP data IRAS/DIRBE


CMB Life after WMAP and its Predecessors CMB Life after WMAP and its Predecessors

The cosmological model has already been fairly tightly constrained

It is, therefore, possible that what is left to be done is “just”– Refinement, refinement, refinement -

For example, Planck polarization measurements, etc.

But, perhaps,– Not all loose ends have been tied up yet -

Does the data already collected tell us something that has not been deciphered yet?


Comparison of low-l spectra from COBE-DMR and Comparison of low-l spectra from COBE-DMR and WMAPWMAP


Is the Universe Is the Universe Probed by the Probed by the CMB at Large CMB at Large Angular ScalesAngular Scales

InterestingInteresting“after” WMAP?“after” WMAP?

Are we at

“the End?”, “the Beginning of the End?”, or

“the End of the Beginning?”

of our approach to understanding the universe through the measurements and interpretation of the CMB anisotropy?


““Simplicity, simplicity - you can already see everything…”Simplicity, simplicity - you can already see everything…”

Are these two views of the CMB sky “equivalent”

Is the universe as isotropic as it “should” be, or as we would like it to be?

Are there novel ways to address such questions with the data now at hand, e.g. WMAP sky maps?


How Can we Test the Isotropy of the Universe? How Can we Test the Isotropy of the Universe?

Eriksen, H.K., Hansen, F.K., Banday, A.J., Lilje, P.B., & Gorski, K.M., 2003, astro-ph/037507 – “Asymmetries in the CMB Anisotropy Field”

Eriksen, H.K., Lilje, P.B., Banday, A.J., & Gorski, K.M., 2003, astro-ph/0310831 – “Estimating N-Point Correlation Functions from Pixelized Sky Maps”

Hansen, F.K. & Gorski, K.M., 2003, MNRAS 344, p.544 – “Fast Cosmic Microwave Background Power Spectrum Estimation of Temperature and Polarization

with Gabor Transforms”

Hansen, F.K., Gorski, K.M., & Hivon, E., 2002, MNRAS, 336, p.1304 – “Gabor Transforms on the Sphere with Applications to CMB Power Spectrum Estimation”

Eriksen, H.K., Banday, A.J., & Gorski, K.M., 2002, A&A, 395, p.409 – “The N-Point Correlation Functions of the COBE-DMR Maps Revisited”

Hivon, E., Gorski, K.M., Netterfield, C.B., Crill, B.P., Prunet, S., & Hansen, F., 2002, Ap.J., 567, p.2 – “MASTER of the CMB Anisotropy Power Spectrum: A Fast Method for Statistical Analysis of Large

and Complex CMB Data Sets”

Wandelt, B.D, Hivon, E.H., & Gorski, K.M., 2001, PhR D, 64, p.3003, – “CMB Power Spectrum Statistics for High Precision Cosmology”


Two Options for Two Options for Analysis of the High Analysis of the High

Resolution Whole Sky Resolution Whole Sky Map of the CMB Map of the CMB

AnisotropyAnisotropyExtract pseudo-alms and pseudo-Cls on the

whole sky less the galactic and foreground source cut - care needs to be taken of the cut geometry effect on the coupling of the harmonic and spectral coefficients

Extract pseudo-alms and pseudo-Cls on the

small disk (less the foreground source cut, if sources present)

- given simple geometry of the boundary of the disk, the coupling

of the harmonic and spectral coefficients can be accounted for exactly


Average Power Average Power SpectraSpectra

Derived on the Whole Derived on the Whole Sky (Sky (redred), and on the), and on the9.5 deg Disk (9.5 deg Disk (greengreen))

“Integrals” of both spectra are equal - the variances of the anisotropy power per pixel on the sky are equal


Analysis of WMAP Sky Maps Analysis of WMAP Sky Maps Cut up into 9.5 deg Disks Cut up into 9.5 deg Disks

164 disks of 9.5 deg radius are placed outside the WMAP Kp2 sky cutFirst, Gabor pseudo-spectra derived on those small disks are used to test the isotropy of the CMB power spectrumSecond, 82 disk center directions are used to define North poles of the reference frames in which pseudo-spectra are derived from the north and south hemispheresCoadded V+W WMAP data are used with the Kp2 sky cut6144 Monte-Carlo simulations of the best fitting running spectrum model and WMAP noise are used for statistical calibration of the results


And the results are …And the results are …

Blue/green dots: total 9.5 degree disk pseudo-power between l=2, and l=63 compared to the theoretical distribution of the best fitting model; >90% events - green, <10% events - blue

Large disks: color coded ratio of north/south hemisphere l=2-63 pseudo-power; low values - yellow, large values - dark red


Localised 3-point correlation function analysisLocalised 3-point correlation function analysis

Intermediate scale three point analysis of the co-added Q+V+W WMAP sky maps (filtered to remove the power at l<18); Kp0 sky cut was applied

3-point functions computed in 460 isocles configurations smaller than 5 deg on a set of 81 disks

C2


WMAP vs. COBE-DMR and Dust Emission of the GalaxyWMAP vs. COBE-DMR and Dust Emission of the Galaxy


ConclusionsConclusions

Usual suspects– Systematic effect

– Foreground effect Galactic? Extra-galactic?

The least likely to be accepted: intrinsic CMB effect

Refutation?– What about the WMAP - DMR consistency:

No common mode systematic effects

– Difficult to explain power deficit in a region of low foreground emission; consistent results across frequencies

There is growing evidence that interesting effects exist, unexpectedly, at rather large angular scales in the WMAP data. Other than this work,

Park (astro-ph/0307469, genus asymmetry), Naselsky et al.(astro-ph/0310235, phase correlations), Coles et al.(astro-ph/0310252,

phase correlations), Vielva et al.(astro-ph/0310273 wavelets), and Copi et al.(astro-ph/0310511, multipole vectors) claim finding various forms of non-gaussianity and north-south asymmetry in the WMAP sky maps.

Some of those claims are statistically stronger than ours.Clearly, there is also a growing need for explanations.


Large-scale anomalies in the WMAP dataLarge-scale anomalies in the WMAP data

Large-scale anomalies in the first-year WMAP data:

1. Low-l multipole alignments and symmetries (l = 2, 3, 5, 6)

2. Large-scale power asymmetry (l < 40)

3. Non-Gaussianity in the northern galactic hemisphere at ~ 3 degree scales

4. Unusually cold spot spanning 10° on the sky at (l,b) = (207°, -59°)

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.


1) Low-1) Low-ll alignments and symmetries alignments and symmetries

First reports:

De Oliveira-Costa et al. 2004, Phys. Rev. D. 69, 063516Bennett et al. 2003, ApJS, 148, 1

End-to-end Monte-Carlo analysis:

Eriksen et al. 2004, ApJ, 612, 633

Multipole vector approach:

Copi et al. 2004, Phys. Rev. D 70, 043515Schwartz et al. 2004, Phys. Rev. D 93, 221301Katz and Weeks, 2004, Phys. Rev. D. 70, 063527Weeks, 2004, preprint, astro-ph/0412231

Claimed anomalies:

1. Low quadrupole amplitude Initially claimed at few percent level; exact calculations show 10%

significance

2. Alignment between l = 2 and l = 3 planes Significance about 98%, independent of method

3. Planar l = 3 and 6 modes; spherically symmetric l = 5 modeSignificance of 1.5, 3 and 2 for l = 3, 5 and 6, respectively

Problem:All results are obtained from full-sky “foreground corrected” maps, which are known to contain residual foregrounds. Cosmological significance remains unclear.

l = 3l = 2

l = 6l = 5


2) Large-scale power asymmetry, 2) Large-scale power asymmetry, ll < 40 < 40

Asymmetry significant at 2.5-3, independent of frequency, galactic cut, and statistic.

Eriksen et al. 2004, ApJ, 605, 14Eriksen et al. 2004, ApJ, 612, 64Eriksen et al. 2004, astro-ph/0407271Hansen et al. 2004, MNRAS, 354, 641Hansen et al. 2004, MNRAS, 354, 905Larson and Wandelt, 2004, ApJ, 613, L85Donoghue and Donoghue, 2004, astro-ph/0411237Etc.

Computed power spectrum from complementary hemispheres in one hundred reference frames

Power spectra in reference frame of maximal asymmetry


Uniform distribution

Many big spots; few small spots

Many small spots; few big spots

3) Hot and cold spot anomaly in the northern galactic hemisphere at ~ 3° scales3) Hot and cold spot anomaly in the northern galactic hemisphere at ~ 3° scales

Threshold atTlim = -40 K

Threshold atTlim = +40 K1) No large cold spots on the

northern hemisphere; another manifestation of the power asymmetry

2) Nhot(40 K) Ncold(-40 K); indication of an intrinsically non-Gaussian distribution

Eriksen et al. 2004, ApJ, 612, 64; Hansen et al. 2004, ApJ, 607, 67Park, 2004, 2004, MNRAS, 349, 313, etc.

Quantitative description -- the genus


4) Cold spot at (4) Cold spot at (ll,,bb) = ) = (207°, -59°)(207°, -59°)

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

• Large, very cold spot was detected using wavelets by Vielva et al.

• Anomalous at the 3 confidence level, compared to Monte Carlo simulations

• Independent of frequency and foreground correction method

First detection:Vielva et al. 2004, ApJ, 609, 22

Confirmations:Cruz et al. 2004, MNRAS, 509, XMukherjee and Wang, 2004, ApJ, 613, 59


ConclusionsConclusions

1. The large-scale features of the WMAP data are currently not properly understood

2. Foregrounds do not seem as a probable explanation for any of the l > 6 effects. Situation still unresolved for the l < 6 alignment and symmetry anomalies

3. Assuming the WMAP data are free of systematics, these detections could possibly point towards new physics.


Sensitivity comparison of Sensitivity comparison of WMAP and PlanckWMAP and Planck


What (we hope) Planck will addWhat (we hope) Planck will addIn addition to wider frequency coverage and better sensitivity than WMAP,

Planck has the resolution needed to see into the damping tail. No other experiment can cover enough sky to make a cosmic variance limited

measurement of the scales around the 3rd and 4th peaks.

(4yr) (1yr)


What (we hope) Planck will addWhat (we hope) Planck will add

A precise measurement of the E-mode polarization power spectrum.


US Planck Algorithm Development GroupUS Planck Algorithm Development Group First Meeting - March 11, 2004

Weekly Telecons, 1/2 day

Monthly Face-to-face Meetings, all-day, regularly at JPL, to be held (occasionally) at other locations

Presently attended by team members from Pasadena, Berkeley, Davis (CA), Urbana/Champaign (IL)

Coordination: KMG

Active Participants:

– Pasadena: E. Hivon, H.-K. Eriksen, G. Prezeau, J. Jewell, S. Levin, E. Pierpaoli,

K.M. Gorski, C. Lawrence, K. Ganga

– Berkeley: J. Borrill, R. Stompor, C. Cantalupo, G. Chon, A. Amblard

– Davis: L. Knox, M. Chu, O. Holm

– Urbana-Champaign: B. Wandelt, C. Armitage, I. O’Dwyer, D. Larson

ADG activity is conducted on the level of effort basis


Map Making from HFI 217 GHz TQU TODsMap Making from HFI 217 GHz TQU TODsInput Data Generated by Level S Simulation Pipeline:

– 217 GHz: 5’ circular beam, 200 Hz sampling

– 4 polarized detectors, 1 year mission: 24 Gsamples of measurements

– Individual detector pointing (double precision) TOD = 1 TB of data TOD = ~550 GB if pointing reformatted

– Stationary Noise 1 / f 2, knee = 30 mHz

– Pointing jitter

– 2 scanning strategies Nominal (i.e., no modulation - misses Ecliptic poles) Cycloidal modulation of spin axis pointing to cover

the whole sky (6 months precession period)

Computing:– Seaborg (NERSC, LBL, Berkeley)

– 2048 CPUs and 2 TB of RAM used

– ~5 hrs execution time

Output: – TQU HEALPix maps, 1.7 arcmin pixels (50 Mpixel/map)


Simulation Parameters and Computational Simulation Parameters and Computational ResourcesResources

Parameters:

Computing:

Detectors 12 @ 217 GHz (8 polarized, 4 unpolarized)

Observations 366 days @ 200 Hz = 6,324,480,000 samples per detector

Noise Properties White + 1/f, 6-day piecewise stationary

Scanning Strategy Cycloidal - slow (6 month) precession

Resolution HEALPix Nside=2048 — 50,331,648 x 1.7' pixels per Stokes parameter

Machine Seaborg at NERSC

Processors 6000 x 375 MHz Power3

Run-time 2hrs wallclock / 12,000 CPU hrs

Memory 4 Tbytes

Disk 2.5 Tbytes


Computing Full Resolution Maximum Likelihood Maps Computing Full Resolution Maximum Likelihood Maps of Complete Single Frequency Planck Dataof Complete Single Frequency Planck Data

The Planck satellite will gather an unprecedented volume of Cosmic Microwave Background (CMB) temperature and polarization data whose analysis will present a major computational challenge.

Christopher Cantalupo, Julian Borrill & Radek Stompor, Computational Research Division, Lawrence Berkeley National Laboratory & Spaces

Sciences Laboratory, UC Berkeley

Temporal correlations in the detector noise mean that maximum likelihood (generalized least squares) methods must be used to obtain the highest fidelity CMB sky maps. Here we have used MADmap - a massively parallel implementation of the preconditioned conjugate gradient solution to maximum likelihood map-making - to make the first optimal, full-resolution, I, Q & U maps from 1 year of simulated data from all of the Planck detectors at a single frequency. (but - Mapcumba …) This calculation (mapping 75 billion observations to 150 million pixels) used 6000 processors of NERSC's Seaborg supercomputer for 2 hours, demonstrating the practicality of processing such data volumes by these methods. Scaling to this concurrency did involve breaking significant MPI and I/O bottlenecks, but the results here show that continued access to state-of-the-art supercomputers, and the development of codes that can exploit their full capabilities, will be of great benefit to Planck science.


Planck Scanning strategyPlanck Scanning strategy


The input CMB signals for these The input CMB signals for these simulations were generated by simulations were generated by

matching spherical harmonics up to matching spherical harmonics up to l = 3000 to the WMAP-extended l = 3000 to the WMAP-extended

data.data.


Full WMAP resolution (Nside 512) Single Frequency (94 GHz) 1st Year Full WMAP resolution (Nside 512) Single Frequency (94 GHz) 1st Year CMB Intensity DataCMB Intensity Data


Full Planck Resolution Single Frequency 1 Year CMB Intensity MapFull Planck Resolution Single Frequency 1 Year CMB Intensity Map


The Same 100 Square Degree Patch Cut From Full-Sky WMAP and The Same 100 Square Degree Patch Cut From Full-Sky WMAP and Planck MapsPlanck Maps


TT Power Spectrum from 12 HFI Detectors at TT Power Spectrum from 12 HFI Detectors at 217GHz217GHz


NASA “Beyond Einstein” Strategic Plan


Concept studies(funded)

Dark Energy Probe (aka SNAP):5Inflation Probe (aka CMBPOL): 3Black Hole Finder: 2

“…The Einstein Probes are currently planned to be fully competed, scientist-led mission opportunities with the goal to launch one such mission every three years, starting about 2010. The order in which the Einstein Probes are flown will be determined by both science priority and technological readiness. An Einstein Probe is envisioned as costing between $350M to $500M (real year $) ...”

NASA’s Beyond Einstein Timeline

Announcementof Opportunity?


Experimental Probe of Inflationary Cosmology (EPIC) Consortium:Charles Beichman Robert Caldwell John Carlstrom Sarah ChurchAsantha Cooray Peter Day Scott Dodelson Darren DowellMark Dragovan Todd Gaier Ken Ganga Walter GearJason Glenn Alexey Goldin Krzysztof Gorski Shaul HananyCarl Heiles Eric Hivon William Holzapfel Kent IrwinJeff Jewell Marc Kamionkowski Manoj Kaplinghat Brian KeatingLloyd Knox Andrew Lange Charles Lawrence Rick LeDucAdrian Lee Erik Leitch Steven Levin Hien NguyenGary Parks Tim Pearson Jeffrey Peterson Clem PrykeJean-Loup Puget Anthony Readhead Paul Richards Ron RossMike Seiffert Helmuth Spieler Thomas Spilker Martin WhiteJonas Zmuidzinas Current Team Leader: James Bock (JPL)

Challenges for a Future Space Mission Instrument Parameters

• All-sky coverage: optimal for GW search• Complete frequency coverage• Control systematic errors• Sensitivity: ~1 Ks, 30x better than Planck• Angular resolution:•2-5 arcmin to clean lensing signal; known lensing and SZ science

Science Goals:• Definitively search for IGB signal• Use lensing signal to measure P(k)• Map scalar signal to cosmic variance


Hivon & Kamionkowski, 2002

IGB(T/S = 0.05)

Lensing

Scalar

We’re soon to learn a great deal more about: • Scalar and lensing signals • Foregrounds • Methodology • Technology

BICEP

DASI QUAD

Planck

WMAP

The Not-So Distant Future


Cosmic Microwave Background Polarization

Scalars = Polarization from physics at decouplingCosmic Shear = Gravitational lensing of CMB by matterIGB = Signal from Inflationary Gravity-wave Background

CMB Polarization Power Spectrum

EPIC = Experimental Probe of Inflationary Cosmology


Future Focal Plane Sensitivities

HEMTs Bolometers TA = 3h/k opt = 50 %/ = 30 % / = 30 % Q&U / feed Qmax/Q0 = 5

& telescope with T = 60 K, = 1%

Future Planck

FreqNET

(calc)

# feeds for

1 uK s

NET

(goal)# feeds

30 38 1500 125 2

45 42 1750 155 3

70 25 750 220 6

100 25 750 55 4

150 25 750 57 4

220 38 1500 95 4

350 290 4

Planck bolos near photon noise limit

Need arrays for improved sensitivity• ~104 detectors for NET = 1 Ks• polarization sensitivity• collimated beams• physically large• no mixed technology focal planes

Current and future focal planes


HEALPixHEALPixHierarchical, Equal Area, iso-Latitude Pixelization of the sphere - a novel data structure and a software package for discretization, and fast global (and local) synthesis and analysis of functions and data on a sphereKMG, E. Hivon (IPAC/Caltech), B.D. Wandelt (UIUC), A.J. Banday (MPA Garching), et al.Used by WMAP, Boomerang, Planck; >300 individual users worldwideAvailable at http://www.eso.org/science/healpix

Krzysztof M. Górski Jet Propulsion Laboratory/Caltech (Warsaw University Observatory)

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