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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
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 2 Another look at comparison to COBE-DMR
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 3 V-Band WMAP data IRAS/DIRBE
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 4 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?
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 5 Comparison of low-l spectra from COBE-DMR and WMAP
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 6 Is the Universe Probed by the CMB at Large Angular Scales Interesting “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?
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 7 “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?
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 8 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”
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 9 Two Options for Analysis of the High Resolution Whole Sky Map of the CMB Anisotropy Extract pseudo- a lm s and pseudo-C l s 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- a lm s and pseudo-C l s 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
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 10 Average Power Spectra Derived on the Whole Sky (red), and on the 9.5 deg Disk (green) “Integrals” of both spectra are equal - the variances of the anisotropy power per pixel on the sky are equal
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 11 Analysis of WMAP Sky Maps Cut up into 9.5 deg Disks 164 disks of 9.5 deg radius are placed outside the WMAP Kp2 sky cut First, Gabor pseudo- spectra derived on those small disks are used to test the isotropy of the CMB power spectrum Second, 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 hemispheres Coadded V+W WMAP data are used with the Kp2 sky cut 6144 Monte-Carlo simulations of the best fitting running spectrum model and WMAP noise are used for statistical calibration of the results
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 12 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
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 13 Localised 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 C 2
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 14 WMAP vs. COBE-DMR and Dust Emission of the Galaxy
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 15 Conclusions 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.
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 16 Large-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°)
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 17 1) Low-l alignments and symmetries First reports: De Oliveira-Costa et al. 2004, Phys. Rev. D. 69, 063516 Bennett 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, 043515 Schwartz et al. 2004, Phys. Rev. D 93, 221301 Katz and Weeks, 2004, Phys. Rev. D. 70, 063527 Weeks, 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 mode Significance 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 = 6 l = 5
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 18 2) Large-scale power asymmetry, l < 40 Asymmetry significant at 2.5-3 , independent of frequency, galactic cut, and statistic. Eriksen et al. 2004, ApJ, 605, 14 Eriksen et al. 2004, ApJ, 612, 64 Eriksen et al. 2004, astro-ph/0407271 Hansen et al. 2004, MNRAS, 354, 641 Hansen et al. 2004, MNRAS, 354, 905 Larson and Wandelt, 2004, ApJ, 613, L85 Donoghue and Donoghue, 2004, astro-ph/0411237 Etc. Computed power spectrum from complementary hemispheres in one hundred reference frames Power spectra in reference frame of maximal asymmetry
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 19 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° scales Threshold at T lim = -40 K Threshold at T lim = +40 K 1)No large cold spots on the northern hemisphere; another manifestation of the power asymmetry 2)N hot (40 K) N cold (-40 K); indication of an intrinsically non-Gaussian distribution Eriksen et al. 2004, ApJ, 612, 64; Hansen et al. 2004, ApJ, 607, 67 Park, 2004, 2004, MNRAS, 349, 313, etc. Quantitative description -- the genus
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 20 4) Cold spot at (l,b) = (207°, -59°) 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, X Mukherjee and Wang, 2004, ApJ, 613, 59
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 21 Conclusions 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.
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 22
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 23 Sensitivity comparison of WMAP and Planck
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 24 What (we hope) Planck will add In 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 3 rd and 4 th peaks. (4yr)(1yr)
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 25 What (we hope) Planck will add A precise measurement of the E-mode polarization power spectrum.
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 26 US 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
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 27 Map Making from HFI 217 GHz TQU TODs Input 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)
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 28 Simulation Parameters and Computational Resources Parameters: Computing: Detectors12 @ 217 GHz (8 polarized, 4 unpolarized) Observations366 days @ 200 Hz = 6,324,480,000 samples per detector Noise PropertiesWhite + 1/f, 6-day piecewise stationary Scanning StrategyCycloidal - slow (6 month) precession ResolutionHEALPix Nside=2048 — 50,331,648 x 1.7' pixels per Stokes parameter MachineSeaborg at NERSC Processors6000 x 375 MHz Power3 Run-time2hrs wallclock / 12,000 CPU hrs Memory4 Tbytes Disk2.5 Tbytes
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 29 Computing Full Resolution Maximum Likelihood Maps of 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.
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 30 Planck Scanning strategy
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 31 The input CMB signals for these simulations were generated by matching spherical harmonics up to l = 3000 to the WMAP-extended data.
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 32 Full WMAP resolution (Nside 512) Single Frequency (94 GHz) 1st Year CMB Intensity Data Full WMAP resolution (Nside 512) Single Frequency (94 GHz) 1st Year CMB Intensity Data
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 33 Full Planck Resolution Single Frequency 1 Year CMB Intensity Map Full Planck Resolution Single Frequency 1 Year CMB Intensity Map
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 34 The Same 100 Square Degree Patch Cut From Full-Sky WMAP and Planck Maps
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 39 TT Power Spectrum from 12 HFI Detectors at 217GHz
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 42 NASA “Beyond Einstein” Strategic Plan
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 43 Concept studies (funded) Dark Energy Probe (aka SNAP):5 Inflation Probe (aka CMBPOL): 3 Black 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 Announcement of Opportunity?
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 44 Experimental Probe of Inflationary Cosmology (EPIC) Consortium: Charles BeichmanRobert CaldwellJohn CarlstromSarah Church Asantha CoorayPeter DayScott DodelsonDarren Dowell Mark DragovanTodd GaierKen GangaWalter Gear Jason GlennAlexey GoldinKrzysztof GorskiShaul Hanany Carl HeilesEric HivonWilliam HolzapfelKent Irwin Jeff JewellMarc KamionkowskiManoj KaplinghatBrian Keating Lloyd KnoxAndrew LangeCharles LawrenceRick LeDuc Adrian LeeErik LeitchSteven LevinHien Nguyen Gary ParksTim PearsonJeffrey PetersonClem Pryke Jean-Loup PugetAnthony ReadheadPaul RichardsRon Ross Mike SeiffertHelmuth SpielerThomas SpilkerMartin White Jonas 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 K s, 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
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 45 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
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 46 Cosmic Microwave Background Polarization Scalars = Polarization from physics at decoupling Cosmic Shear = Gravitational lensing of CMB by matter IGB = Signal from Inflationary Gravity-wave Background CMB Polarization Power Spectrum EPIC = Experimental Probe of Inflationary Cosmology
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 47 Future Focal Plane Sensitivities HEMTsBolometers T A = 3h /k opt = 50 % / = 30 % / = 30 % Q&U / feedQ max /Q 0 = 5 & telescope with T = 60 K, = 1% FuturePlanck Freq NET (calc) # feeds for 1 uK s NET (goal) # feeds 303815001252 454217501553 70257502206 10025750554 15025750574 220381500954 3502904 Planck bolos near photon noise limit Need arrays for improved sensitivity ~10 4 detectors for NET = 1 K s polarization sensitivity collimated beams physically large no mixed technology focal planes Current and future focal planes
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Zeldovich 90 Moscow, 20-24 Dec. 2004K.M. Gorski - 48 HEALPix Hierarchical, 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 sphere KMG, E. Hivon (IPAC/Caltech), B.D. Wandelt (UIUC), A.J. Banday (MPA Garching), et al. Used by WMAP, Boomerang, Planck; >300 individual users worldwide Available at http://www.eso.org/science/healpixhttp://www.eso.org/science/healpix
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