CMB polarization and cosmology

Transcription

1 Fundamental physics and cosmology CMB polarization and cosmology Institut d'astrophysique Spatiale Orsay

2 Standard cosmology : reverse the expansion GeV GUT s GeV s 300 GeV 0.1 MeV 1 ev 0.1 ev Z=1000 E-W W Transition Nucleosynthesis Matter-Radiation equality s 100 s 10 4 yrs 10 5 yrs Theoretical extrapolations (high energy) Known Physics (low energy) Z=20? Reionization Remarkable achievements : Z=10 Galaxies Light elements abundance prediction Z=4 Z=0 0.2 mev Clusters yrs Existence and correct temperature of the CMB

3 Problems High energy symetry breakings generate magnetic monopoles, stables, heavy: ~10 16 GeV Ò Mm ý Ò tot t 0 CMB A Causal Horizon A B Causal Horizon B 2. We now measure: Ω tot 1 jò tot (10 à43 sec) à 1j ô O(10 à60 ) 3. Causal distance in the sky: 1 deg ÉT=T ø 10 à5 Observer 4. Large scale structures generation in an isotropic and homogeneous universe.

4 The Inflation C GeV GUT s GeV s 300GeV 0.1MeV 0.1eV Z=1000 1eV GUT E-W W Transition Nucleosynthesis Matter-Radiation equality CMB z =1000 Inflation s 100s 10 4 yrs 10 5 yrs A B Inflationary causal horizon Z=20? Z=10 Z=4 Z=0 0.2meV Reionization Galaxies Clusters yrs Observer 1. Monopoles diluted 2. Ω = 1 predicted 3. Diverging horizon 4. Perturbations generation mechanism

5 Basic mechanism Scalar field going down to its minimum The Reheating sets the end of Inflation and the beginning of the standard expansion Main constraints : Large scale structures Primordial nucleosynthesis CMB Kolb & Turner

6 High Energy Physics The gravitino (ψ µ ) problem Stable Unstable 10 ev 1 kev 1 GeV 100 GeV 1 TeV GMSSB n 3=2 / T RH Inflation GUT msugra T RH < GeV 10 TeV m 3/2 T RH GeV + polarization Incompatible with a detection of tensor modes except in the Thermal inflation scenario. + constraints on m 3/2 with primordial black holes Barrau & NP, 2004, PRD

7 fundamental physics and cosmology inflation string theory : extra dimensions, branes, cyclic universe physics beyond the standard model : supersymetry (dark matter) dark energy

8 CMB T 0 = ± (95% CL) ÉT T 0 (ò; þ) = P lm a lmy lm (ò; þ) ha lm a? l 0 m 0i =C l î ll 0î mm 0 1 Cê l = P 2l+ 1 m j a lm j 2 Sensitive to cosmological parameters accuracy ~ % but Degeneracies Cosmic Variance

9 WMAP, février 2003 Bennett et al, 2003 WMAP + ACBAR + CBI + 2dF + Lyα Ω tot = 1.02 ± 0.02 Ω Λ = 0.73 ± 0.04 Ω m = 0.27 ± 0.04 Ω b = ± n s = 0.93 ± 0.03 Confirmation of Standard ΛCDM (?) et τ = 0.17 ± 0.04

10 CMB polarization Temperature alone leaves degeneracies T Variation of n T Break of degeneracies Window on Inflation Neutrinos mass Primordial Universe : light on GUT, SuSy Barrau & NP, 2004, PRD

11 Recombination Thomson scattering : dσ/dω ~ ε.ε 2 Isotropic radiation (monopole) x y z ε e - y ε x z No polarization

12 Recombination Thomson scattering : dσ/dω ~ ε.ε 2 Dipole x y z ε e - y ε x z No polarisation

13 Recombination Thomson scattering : dσ/dω ~ ε.ε 2 Quadrupole x y z ε e - y ε x z Polarization

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15 CMB : global description (QæiU) 0 (nê) =e ç2i (Q+ iu)(nê) Projection (QæiU)(nê) = P lm a æ2;lmy æ2;lm (nê) y y x ψ x Algebra E < 0 E > 0 E= P lm ae lm Y lm B= P lm ab lm Y lm B < 0 B > 0 Newman & Penrose, (1966), J. Math. Phys., 7, 863 Seljak & Zaldarriaga, (1997), PRD 55, 1830

16 Simplest inflation predictions spectral index n s close to 1: n s -1 = -3(1+w)~0.05 directly related to w=p/ρ 1: 1+w ~ 0.02 primordial gravitational waves produce B mode polarization inflation energy scale ~ GUT tensor to scalar fluctuations: r~20 to 30 % In cyclic universe r is very low

17 CMB polarization spectra 3 observables : T, E, B 6 spectra : TT, EE, BB, TE, TB, EB T, E : scalars B : pseudo-scalars TB, EB = 0 1 to 4 orders of magnitude weaker than T

18 lensing of the CMB lensing by dark matter structures at low z produces B mode polarization at sub degree scales depends on the structure depends on the expansion rate (which in turn affects the structure development) lensing of CMB is a probe of dark energy complementary to weak lensing on galaxies

19 Neutrinos masses Oscillations experiments are only sensitive to the squared mass difference between the different neutrinos Massive neutrinos cluster on large scale but free-stream on small scale Modification of the mass spectrum + non gaussian signature in the polarization B mode WMAP (TT) + cosmo : m ν < 0.23 ev B mode: m ν < 0.05 ev Kaplinghat et al, 2002

20 Experimental results 1 measurement EE (DASI) TE, WMAP Kovac et al, 2002 Upper limits Reionization EE TE de Oliveira Costa et al, 2002 Kogut et al, 2002

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22 Planck can detect the tensor modes if inflation energy scale is the GUT scale (10 16 GeV) Planck W. Hu

23 Future experiments Dedicated CMB polarization satellite : EPIC Important efforts invested in the quest for CMB polarization Systematics and foregrounds!

24 Planck mission concept Planck conceived to be limited by foregrounds for T measurements instantaneous sensitivity limited by photon noise (cryogenic detectors), total power measurements ` broad frequency coverage: 30 GHz to 1 THz (2 technologies) 5 arc minutes resolution for the best CMB channels polarization measurements in a very broad range For Polarization Planck will be sensitivity limited but the broad frequency coverage (30 GHz-353 GHz) should be very good for foregrounds half way between WMAP and an inflation probe mission `

25 Focal Plane Unit Focal Plane System is FPU without horns, filters, bolometers it does include blind bolometers and all thermometers 25

26 FPS at Air Liquide

27 Planck planned capabilities

28 Planck Polarized planned capabilities (and comparison to WMAP) sensitivity for 20 arcmin pixels, Planck:14 months WMAP: 2 years

29 Measured performances: HFI bolometers in specs (most time constants close to the goals, a few at the specification level, NEP below or within 10% of the photon noise) excellent total optical efficiency measured in the ARCHEOPS flight (better than 40%) read out electronics: no 1/f noise down to 10-2 Hz many aspect of the Planck HFI concept have been tested with the ARCHEOPS balloon borne experiment

30 spectra on Archeops coverage linear fit with error bars in both coordinates nside nside = fcut(archeops) = 0.1/38 0.1/38 Hz Hz nopond chi2 chi2 = 23.6/24 goodness of of fit fit q =

31 Foregrounds GHz Bremsstrahlung: Electrons are deviated by ISM atoms Synchrotron: Electrons are deviated by the galactic magnetic field Dust: Dust is heated by nearby stars and radiates in the IR and submm domains Significant contribution wrt the CMB + polarization

32 Archeops maps Feb 7 th hours of night data First submillimetric maps at 15 arcmin resolution, 30% sky 545 GHz 550 µm 353 GHz 850 µm Polarized 217 GHz 1.4 mm 143 GHz 2.1 mm

33 7 Gemini 10 9 Taurus Cassiopeia P (%) θ (deg) (Stat,syst) 12.1 ± 1.8 ± ± 4.7 ± ± 0.7 ± ± 2.8 ± ± 3.4 ± ± 0.9 ± ± 6.7 ± ± 2.9 ± ± 1.7 ± ± 3.7 ± ± 3.6 ± ± 7.5 ± ± 6.7 ± ± 3.2 ±1.1 Taurus 5.3 ± 3.1 ± ± 2.8 ±4.1 < ± 13.6 ± ± 11.5 ± ± 16 ± 105

34 Diffuse radiation 5 deg wide bands (except edges) Values scaled to mean intensity over -2 < b < 2) Orientation mainly orthogonal to the galactic plane P ~ 3-5% on average

35 Archeops / Polarization Dust will be the major foreground for CMB temperature measurements at high frequencies Fosalba et al 2002, ApJ, 564, 762 Serkowski et al Heiles Expectation of at least 3% in submm Stein 1966, ApJ, 144, 318 No measurement on large scales available yet

36 Importance of foregrounds for very sensitive polarization measurements: the synchrotron spectral index is variable The dust polarization is high the dust emission long wavelenths spectrum is somewhat flatter than expected

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39 noise power spectrum of the electronic detection chain QM (REU + PAU + J-FET) nominal noise 7nV/Hz 1/2

40 Blind bolometer on the Qualification model of the FPS cooled to 98mK

41 ARCHEOPS as a Planck HFI demonstrator ARCHEOPS is a balloon borne experiment with a Planck HFI type focal plane same bolometers, horns, filters, dilution cooler, total power readout electronics Planck telescope, about 10 arc minutes resolution He cryostat scanning strategy similar to Planck spinning at 2 RPM capability to cover 1/3 of the sky in one flight

42 RESULTS I (353 GHz) Gemini Cygnus Taurus Cassiopeia 17% of sky, Galactic anticenter mk RJ Smoothed, 1deg

43 Signal to noise (Q 2 + U 2 )/(σ Q2 + σ U2 ) 1σ 1.1 2σ 3.1 3σ 5.8 Smoothed, 1deg

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45 Mode B tensor spectral index n T ΛCDM : n T = -0.3, -0.2, -0.1, 0, 0.1, 0.2 T TE E Variance cosmique B