Present and (near) future CMB observations from space Marco - PowerPoint PPT Presentation

San Servolo, Venezia – 27-31 August 2007 – A Century of Cosmology: Past, Present and Future Present and (near) future CMB observations from space Marco Bersanelli University of Milano San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

“For their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation” COBE-FIRAS COBE-DMR John C. Mather George F. Smoot Cosmic Background Explorer New discovery High precision San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Expected CMB power spectrum l ∑ ∑ 1 2 Δ ϑ φ = ϑ φ = = 2 T ( , ) a m Y ( , ) C a a l l l l l m m + m l 2 1 = − l l m m Angular scale Θ Θ = 180° Θ = Θ 1 ≈ 1° Θ = Θ 2 ≈ 0.1° Θ → 0° Anisotropy ( μ K 2 ) Acoustic peaks Primordial fluctuations < l 20 Damping DMR Beyond Horizon Within Horizon l = 1 l ≈ 180 l ≈ 2000 l → ∞ Multipole l = π / Θ San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

The details of the angular power spectrum depend on the value of the main cosmological parameters Ω = Ω + Ω + Ω Ω Λ Λ 0 M R Ω Ω M B Accurate high resolution measurements of CMB anisotropies lead to high precision determination of parameters San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Before and after WMAP WMAP 3yr T power spectrum and TE correlation (Hinshaw et al 2006) All measurements before WMAP (Dec 2002) San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

WMAP 1.4 × 1.6 m primary reflectors Upper omni antenna COBE-DMR Heritage Dual back-to-back Greforian optics Focal plane assembly (95K) Feed horns Secondary reflector Passive thermal radiator Warm S/C and Thermally isolating instrument electronics cylinder (300K) Reaction wheels Star tracker • Coherent detection • Differential receiver • Spinner • Passive cooling Deployed solar array & schield San Servolo, Venezia – 27-31 August 2007 M.Bersanelli – Present and (near) future CMB observations from space

WMAP Instrument Assembly Pseudo-correlation HEMT coherent radiometers Instrument Front-end Assembly WMAP W-band feed horn Università di MIlano

WMAP 3yr data: Systematics analysis (Jarosik et al 2006) The success of WMAP (and COBE) rests on accurate control of systematic effects 1. Window function determination WMAP 3yrs: six Jupiter-crossing data sets Beam solid angles found 1% larger than assumed in 1st year (1.5% effect on power spectrum). 2. Radiometer gain model 1st yr model If not corrected, would lead to ∼ mK Gain data effect on maps New model San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Foregrounds • WMAP 3-yr data confirmed minimum of foreground contamination to T and Polarisation fluctuations is at ~ 70 GHz; • Polarisation: even at optimal frequencies, signal (on average) is dominated by polarized galactic signal • foregrounds are a serious challange San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Design goals • Angular resolution: ~10’ • Sensitivity per pixel: < 10 μ K • Full frequency range: 30-900 GHz • Polarisation sensitive in CMB channels • Sky coverage: 100% • High control of systematics Two complementary cryogenic instruments in focal plane: LFI: Radiometer array (20K) HFI: Bolometer array (0.1K) Planck Scientific Programme, ESA-SCI(2005)1 (“Blue book”) San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Precision cosmology with Planck: Temparature anisotropy ESA-SCI(2005)1 (“Blue book”) San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Planck & CMB polarisation ESA-SCI(2005)1 (“Blue book”) E-mode polarisation power spectrum Searching for B-mode component r = 0.1 San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

~ 13.7 years ago ~ 13.7 years ago

Planck SVM, Telescope & Instruments Integration

Planck Collaboration: ~ 400 scientists! Planck Science Team: J. Tauber (ESA PS), M. Bersanelli, F. Bouchet, G. Efstathiou, J.M. Lamarre, C. Lawrence, N.Mandolesi, H.U. Norgaard-Nielsen, J.-L. Puget, A. Zacchei San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Planck CQM PPLM 45K Primary r ef lect or 45K Ellissoidal 1.5 x 1.9 m 50K 100K V-grooves 150K Focal SVM plane 300K 20K unit 4K 0.1K Sub-ref lect or Ellissoidal ∼ 1 m

Planck Instruments – Calibration Plan Unit Assembly Instrument Satellite In-flight LFI HFI Qualification Model (QM) Qualification Model (QM) Completed Completed Completed Completed Completed Completed Completed Completed Flight Model (FM) Flight Model (FM) On-going I n preparation Completed Completed On-going I n preparation Completed Completed Completed Completed Supported by Data Processing Centers Supported by Data Processing Centers San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

LFI FM cryo testing LFI FM cryo testing Waveguides Waveguides Back-end unit Back-end unit Front-end unit Front-end unit Blackbody calibrator Blackbody calibrator

HFI FM cryo testing HFI FM cryo testing integrating sphere integrating sphere blackbody sources blackbody sources Planck/HFI PFM Planck/HFI PFM polarizer optical system polarizer optical system 2K Saturne plate 2K Saturne plate

Long-duration LFI-RAA data set 45 hours of undisturbed acquisition (MODE 5) 70 GHz LFI# 19 02 Sep 2006 San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Long-duration LFI-RAA data set 45 hours of undisturbed acquisition (MODE 5) 70 GHz LFI# 19 02 Sep 2006 10 mHz Knee frequency ~ 10mHz San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Amplitude spectral density comparison (internal consistency) Basic model: Radiometer Equation Single diode Combined diode Unchopped data Solid line = WN best fit Dashed line = Sqrt(2)* WN - Excellent consistency of measured noise ASD with expected behaviour - LFI differential receiver design provides ~ 10 3 rejection of radiometer instability San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

70 GHz sensitivity to polarisation signals Data stream: DAE0027, FM 70 GHz RCA21 Temperature and Polarisation time streams compared with relative change in T of the loads during the test. T= (A+ B) + (C+ D) P= (A+ B) – (C+ D) Tsky – Tref (sensor) No significant T bleeding into the P signal San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

HFI Cryogenic testing 100mK stability during the calibration run 100mK1 PID2N • 12/7 at 0h00 • T= 100mK • PID2 was off • Requirements are met down to 0.1Hz • Low frequency stability probably limited by the environment San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

HFI Cryogenic testing 100mK stability during the calibration run 143 GHz channel noise properties Long timescale drifts correlate well with Saturne thermometry � field SPHERE_MONIT_ISC2_TE MP interpolated and smoothed � fit to bolometer data using linear regression and subtracted from raw, despiked bolometer timestreams San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Control of Systematic effects • At Planck sensitivity, systematics must be controlled at μ K level • LFI/HFI cross-correlation (e.g. 70 vs 100 GHz) is a key tool to be exploited against systematics • Essential element of data processing strategy ⎛ ⎞ πν τ ν sin( ) N 1 ∑ ⎜ ⎟ − = π f f 1 F cos 2 j ⎜ ⎟ πν τ ν N ⎝ ⎠ = j 1 f spin San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

RFQM measurement campaign – QM mirrors and representative FPU and limited number of frequencies – At room temperature All beams computed with Grasp9 (nominal surfaces and alignment) –Main beams –Intermediate beams –Full sky beams San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

RFQM results at 100GHz Alcatel-Alenia Space; ESA; HFI + LFI Teams X-polarisation beam at 100GHz Co-polarisation beam at 100GHz Main beam San Servolo, Venezia – 27-31 August 2007 A Century of Cosmology: Past, Present and Future

Planck-LFI vs WMAP (V-band) WMAP 15 months LFI 15 months Cosmic variance limit Estec, 11-12 April 2006 – M.Bersanelli LFI PST-27 LFI Instrument Report

Planck-LFI vs WMAP (V-band) WMAP 4yr 8yr 1yr LFI 15 months Cosmic variance limit Estec, 11-12 April 2006 – M.Bersanelli LFI PST-27 LFI Instrument Report

Planck-HFI vs WMAP (W-band) 1yr WMAP 4yr 8yr HFI 15 months Cosmic variance limit Estec, 11-12 April 2006 – M.Bersanelli LFI PST-27 LFI Instrument Report

Third V-groove: T <50K Planck CQM tests

Planck SVM