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K. Ganga – CMB Science and Observations 1 Rencontres du Vietnam /08/09 CMB Science and Observations K. Ganga

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K. Ganga – CMB Science and Observations 2 Rencontres du Vietnam /08/09 The CMB The CMB is a blackbody at T = 2.73 K. The most prominent anisotropy in the CMB, with amplitude of about 0.1%, is due to our motion with respect to the CMB rest frame. Further anisotropies are at the level of 0.001% and lower (or much lower)

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K. Ganga – CMB Science and Observations 3 Rencontres du Vietnam /08/09 Observer z =1000z = infinity Plasma Recombination T=2.73K Plasma Horizon ~1 o z =1000 Plasma Recombination Gravitational lensing T=2.73K Reionisation Observer The CMB again... Thanks to A. Taylor

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K. Ganga – CMB Science and Observations 4 Rencontres du Vietnam /08/09 T on super-horizon scales (>1 o ) Sachs-Wolfe Effect: Gravitational redshift due to photons climbing out of potential wells, A. Taylor

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K. Ganga – CMB Science and Observations 5 Rencontres du Vietnam /08/09 Acoustic Oscillations

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K. Ganga – CMB Science and Observations 6 Rencontres du Vietnam /08/09 Measuring Curvature Flat Close d Open Acoustic horizon (same for all) v s t dec J. Ruhl B. Crill

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K. Ganga – CMB Science and Observations 7 Rencontres du Vietnam /08/09 Baryons change the effective mass W. Hu

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K. Ganga – CMB Science and Observations 8 Rencontres du Vietnam /08/09 How Parameters are Fit Parameters are found by making spectra for the range of models of interest and finding which has the best chi-squared given the actual data and some prior information. Angular spectrum varies mostly with b cdm H 0, n s

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K. Ganga – CMB Science and Observations 9 Rencontres du Vietnam /08/09 'Degeneracies' require other data l peak /2 Simulated Pretty flat models tot = 1

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K. Ganga – CMB Science and Observations 10 Rencontres du Vietnam /08/09 A little help from our friends... From: Lewis & Bridle 2002 Red: Pre-WMAP CMB data Blue: CMB data w/ HST Yellow: CMB data w/ HST, 2dF, BBN

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K. Ganga – CMB Science and Observations 11 Rencontres du Vietnam /08/09 The CMB Temperature Power Spectrum Archeops/ARGO/ATCA/BAM/DASI/ DMR/FIRS/IAB/MAX(IMA)/OVRO/ Python/QMAP/Relict/Saskatoon/ South Pole/Tenerife/Toco/Viper/ White Dish/... WMAP/ Acbar/ BOOMERanG/ CBI/ VSA

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K. Ganga – CMB Science and Observations 12 Rencontres du Vietnam /08/09 Quadrupole Scattering e-e- CMB polarization is caused by Thomson scattering of a local quadrupole (Rees, 1968). The polarized component of the CMB must be small, as it results from local temperature anisotropies.

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K. Ganga – CMB Science and Observations 13 Rencontres du Vietnam /08/09 Polarization has been measured Lens IGW DASI, CBI, BOOMERanG and CAPMAP have all published polarization detections. DASI WMAP

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K. Ganga – CMB Science and Observations 14 Rencontres du Vietnam /08/09 Parameters

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K. Ganga – CMB Science and Observations 15 Rencontres du Vietnam /08/09 Can decompose Q & U into: E-modes (even-parity): (or grad) B-modes (odd-parity): (or curl) E-modes produced by all quadrupole sources (velocity gradients and gravitational waves) B-modes produced by gravitational waves and lensing of E-modes The E/B Decomposition Pure EPure B Wayne Hu

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K. Ganga – CMB Science and Observations 16 Rencontres du Vietnam /08/09 Lensing transform E to B Converts E-modes to B-modes – Confusion limit to measuring the gravitational wave component – Interesting signal in itself, probing growth of structure from present-day to epoch of decoupling

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K. Ganga – CMB Science and Observations 17 Rencontres du Vietnam /08/09 Inflation Constraints V E inflation ~ m pl ×r ¼ Liddle & Lyth, 2000

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K. Ganga – CMB Science and Observations 18 Rencontres du Vietnam /08/09 Predicted Spectra TT EE Lens T/S=0.005 T/S=0.05 T/S= BB IGW

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K. Ganga – CMB Science and Observations 19 Rencontres du Vietnam /08/09 Future Observations Lawrence, C.R., Proceedings of Science (CMB2006)

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K. Ganga – CMB Science and Observations 20 Rencontres du Vietnam /08/09 Sensitivity to Q or U ( K s 1/2 ) HFI spec CMB BLIPCMB + Inst. BLIP No of feeds per Q (or U) Beam (arcmin) Frequen cy (GHz) The Planck HFI 50 feeds in a focal plane of ~ 1kg at 100mK Focal plane area ~ 2 square degrees Instantaneous sky coverage per polarization- sensitive frequency about: 0.1 square degrees The HFI also has channels at 100, 545 and 850 GHz that are not polarization sensitive

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K. Ganga – CMB Science and Observations 21 Rencontres du Vietnam /08/09 Predicted Planck Measurements r=0.1,τ=0.17

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K. Ganga – CMB Science and Observations 22 Rencontres du Vietnam /08/09 How to go deeper Planck can detect r~0.1 Planck is ~2 times BLIP Planck has ~10 detectors covering ~0.1 degree 2 per frequency Planck observes ~1 yr. In the BLIP limit, ignoring cosmic variance, Δr~ σ 2 ~(N detectors Time) -1 A future mission should: – Achieve BLIP – Observe longer (~2) ~2 for satellites John will discuss ground- based – Use many more pixels To go much deeper, we must use arrays.

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K. Ganga – CMB Science and Observations 23 Rencontres du Vietnam /08/09 Example: EPIC J. Bock

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K. Ganga – CMB Science and Observations 24 Rencontres du Vietnam /08/09 WMAP Foregrounds 74.3% of sky

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K. Ganga – CMB Science and Observations 25 Rencontres du Vietnam /08/09 BOOMERanG and CBI Measurements Montroy, et al. Neither BOOMERanG nor CBI have detected any BB at the level of the EE polarization signals. This limits the foregrounds in their regions.

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K. Ganga – CMB Science and Observations 26 Rencontres du Vietnam /08/09 Fin

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K. Ganga – CMB Science and Observations 27 Rencontres du Vietnam /08/09 Symmetry?

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K. Ganga – CMB Science and Observations 28 Rencontres du Vietnam /08/09 WMAP: w versus k

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K. Ganga – CMB Science and Observations 29 Rencontres du Vietnam /08/09 WMAP: w versus m

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