Experimental Probe of Inflationary Cosmology

Transcription

1 Experimental Probe of Inflationary Cosmology Issues of Technology Development and Challenges Jamie Bock Jet Propulsion Laboratory JPL Talso Chui Peter Day Clive Dickenson Darren Dowell Mark Dragovan Todd Gaier Krzysztof Gorski Warren Holmes Jeff Jewell Bob Kinsey Charles Lawrence Rick LeDuc Erik Leitch Steven Levin Mark Lysek Sara MacLellan Hien Nguyen Celeste Satter Mike Seiffert Hemali Vyas Brett Williams The EPIC Consortium Caltech/IPAC Charles Beichman Sunil Golwala Marc Kamionkowski Andrew Lange Tomotake Matsumura Tim Pearson Anthony Readhead Jonas Zmuidzinas UC Berkeley/LBNL Adrian Lee Carl Heiles Bill Holzapfel Paul Richards Helmut Spieler Huan Tran Martin White Cardiff Walter Gear Carnegie Mellon Jeff Peterson U Chicago John Carlstrom Clem Pryke U Colorado Jason Glenn UC Davis Lloyd Knox Dartmouth Robert Caldwell Fermilab Scott Dodelson IAP Ken Ganga Eric Hivon IAS Jean-Loup Puget Nicolas Ponthieu UC Irvine Alex Amblard Asantha Cooray Manoj Kaplinghat U Minnesota Shaul Hanany Michael Milligan NIST Kent Irwin UC San Diego Brian Keating Tom Renbarger Meir Shimon Stanford Sarah Church ATK Space Dustin Crumb USC Aluizio Prata

2 Phase 1 report now available ArXive (192 pages) Phase 2 study now underway Part of the CMB mission concept proposal (S. Meyer, PI) Input for decadal presentation This is an entirely open study We d appreciate your input!

3 EPIC: A Scan-Imaging Polarimeter Scan detectors across sky to build CMB map Simple technique. Established history in CMB. Scaling to higher sensitivity Better arrays Adapt this technique for precision polarimetry EPIC mission concept Simple flexible architecture High sensitivity and wide band coverage Two optical configurations for low and high angular resolution Boomerang QUaD Planck Polarbear Maxipol BICEP EBEX Spider PAST ACTIVE NEAR-FUTURE IN DEVELOPMENT

4 Mission Design Challenges COBE 10 mk s 3 bands Need large sensitivity gain over Planck - large format bolometer (or MKID) arrays Foreground subtraction - multiple bands, high sensitivity WMAP 200 μk s 5 bands Control systematic errors - Goal: control raw effects 10x below noise - Req t: remove effects below r = see EPIC talk from Systematics Workshop Planck 10 μk s 7(9) bands? Einstein IP ~1 μk s ~8 bands

5 Advantages of Bolometers Sensitivity - State-of-the-art bolometer NEPs already exceed blip NEP - Formats limited only by optics throughput Band Coverage - Cover all frequencies of interest for CMB in a single technology - Enhanced ancillary science? - Bands and formats are flexible Maturity!? - Planck demonstrates detectors and readouts: a minimum baseline coolers and thermal stability working solutions to many systems issues - Adapt these technologies for the most powerful mission

6 Study of Two Implementations EPIC-LC EPIC-CS Science IGW B-modes IGW B-modes Lensing B-modes BB & EE to cosmic var. 3.5 m Aperture Resolution 6 x 30 cm 0.9 at 90 GHz Galactic + more 280 cm 5 at 100 GHz 13 m Frequency GHz GHz EPIC-LC Low-Cost Design Life Mass (CBE) Cost 2 years 1300 kg $660M (FY07$) 4 years 3500 kg No assessment EPIC-CS Comprehensive Science High-TRL 830 NTD Ge bolometers Upscope 2366 TES bolometers

7 Sensitivity and Angular Resolution Statistical sensitivity in Δl/l = 0.3 bins No foreground removal No systematic errors Small Mission (High TRL) 6x30cm apertures Δθ = 1 at 90 GHz 1-year lifetime 830 NTD Ge Large Mission 2.8 m aperture Δθ = 5 at 90 GHz 2-year lifetime 1520 TES Small Mission 2-year lifetime 2366 TES

8 Sensitivity After Foreground Removal Small Mission (High TRL) 6x30cm apertures 1-year lifetime 830 NTD Ge Sensitivity and Band Small Mission 2-year lifetime 2366 TES Coverage are Important! Amblard, Cooray & Kaplinghat 2007, Phys. Rev. D 75,

9 Focal Plane Sensitivity Budget Detector Sensitivities NEP [aw Hz -1/2 ] Noise Contributions CMB Optics/Baffle Detector Margin Total NET/feed [uk s 1/2 ] Planck-LFI Planck-HFI TFCR-HEMT TFCR-bolo EPIC-CS Perfect bolo Freq [GHz] Freq [GHz] EPIC Sensitivity Assumptions Focal plane temperature Lens temperature Mirror temperature Mirror emissivity at 1 mm Bolometer pitch T 0 T lens T opt ε d/fλ 0.1 K 4 K 60 K 1.0 % 2 Optical efficiency Fractional bandwidth Noise margin Mission lifetime TES safety factor η opt Δν/ν T life P sat /Q 40 % 30 % years 5

10 Focal Plane Sensitivity Budget NEP [aw Hz -1/2 ] CMB Optics/Baffle Detector Margin Total Noise Contributions Freq [GHz] NET/feed [uk s 1/2 ] Detector Sensitivities TFCR 2010 projections 3xQL Δν/ν = 20 % Sim. Q&U Freq [GHz] Planck-LFI Planck-HFI TFCR-HEMT TFCR-bolo EPIC-CS Perfect bolo Δν/ν = 25 % ηopt = 40 % 1.5 KRJ Tc = 300 mk Psat/Q = 3 EPIC-CS Sensitivity Assumptions Focal plane temperature Lens temperature Mirror temperature Mirror emissivity at 1 mm Bolometer pitch T 0 T lens T opt ε d/fλ 0.1 K 4 K 60 K 1.0 % 2 Optical efficiency Fractional bandwidth Noise margin Mission lifetime TES safety factor η opt Δν/ν T life P sat /Q 40 % 30 % years 5

11 Focal Plane Sensitivity Budget Detector Sensitivities NEP [aw Hz -1/2 ] Noise Contributions CMB Optics/Baffle Detector Total NET/feed [uk s 1/2 ] Planck-LFI Planck-HFI TFCR-HEMT TFCR-bolo EPIC-CS Perfect bolo Freq [GHz] Freq [GHz] EPIC-CS Sensitivity Assumptions Focal plane temperature Lens temperature Mirror temperature Mirror emissivity at 1 mm Bolometer pitch T 0 T lens T opt ε d/fλ 0.1 K 4 K 60 K 1.0 % 2 Optical efficiency Fractional bandwidth Noise margin Mission lifetime TES safety factor η opt Δν/ν T life P sat /Q 40 % 30 % years 5

12 Focal Plane Sensitivity Budget Detector Sensitivities NEP [aw Hz -1/2 ] Noise Contributions CMB Optics/Baffle Detector Total NET/feed [uk s 1/2 ] Planck-LFI Planck-HFI TFCR-HEMT TFCR-bolo EPIC-CS Perfect bolo Freq [GHz] Freq [GHz] EPIC-CS Sensitivity Assumptions Focal plane temperature Lens temperature Mirror temperature Mirror emissivity at 1 mm Bolometer pitch T 0 T lens T opt ε d/fλ 0.1 K 4 K 60 K 1.0 % 2 Optical efficiency Fractional bandwidth Noise margin Mission lifetime TES safety factor η opt Δν/ν T life P sat /Q 70 % 30 % years 5

13 Focal Plane Sensitivity Budget Detector Sensitivities NEP [aw Hz -1/2 ] Noise Contributions CMB Optics/Baffle Detector Total NET/feed [uk s 1/2 ] Planck-LFI Planck-HFI TFCR-HEMT TFCR-bolo EPIC-CS Perfect bolo Freq [GHz] Freq [GHz] EPIC-CS Sensitivity Assumptions Focal plane temperature Lens temperature Mirror temperature Mirror emissivity at 1 mm Bolometer pitch T 0 T lens T opt ε d/fλ 0.1 K 2 K 60 K 1.0 % 2 Optical efficiency Fractional bandwidth Noise margin Mission lifetime TES safety factor η opt Δν/ν T life P sat /Q 70 % 30 % years 5

14 Focal Plane Sensitivity Budget Detector Sensitivities NEP [aw Hz -1/2 ] Noise Contributions CMB Optics/Baffle Detector Total NET/feed [uk s 1/2 ] Planck-LFI Planck-HFI TFCR-HEMT TFCR-bolo EPIC-CS Perfect bolo Freq [GHz] Freq [GHz] EPIC-CS Sensitivity Assumptions Focal plane temperature Lens temperature Mirror temperature Mirror emissivity at 1 mm Bolometer pitch T 0 T lens T opt ε d/fλ 0.05 K 2 K 60 K 1.0 % 2 Optical efficiency Fractional bandwidth Noise margin Mission lifetime TES safety factor η opt Δν/ν T life P sat /Q 70 % 30 % years 3

15 Focal Plane Sensitivity Summary Band Sensitivities and Foregrounds T [nk CMB] Δ WMAP-10 Planck-LFI EPIC-small EPIC-large Synch 75 % of sky Dust 75 % of sky Synch 2 % of sky Planck-HFI Dust 2 % of sky Sensitivities ΔT CMB (1σ) in 1 x1 pixel WMAP flight 10 years Planck ground 2 years EPIC projected 2 years Foregrounds Estimated RMS for l= Synch: WMAP-22 & β=-2.8 Dust: FDS and P = 5 % Freq [GHz]

16 Mission Design Options: Small Configuration Deployed Sunshield 40 K Liquid Helium Cryostat (450 l) Six 30 cm Telescopes at 2 K 100 K 100 mk Focal Plane Array 295 K 155 K 8 m 3-Stage V-Groove Radiator Commercial Spacecraft Solar Panels Toroidal-Beam Antenna Main Features Frequency Bands GHz Orbit L2 Halo Resolution 0.9 at 90 GHz Inflow Data Rate 1.3 Mbps Detectors 2366 TES bolometers Total Mass (CBE) 1320 kg Design Lifetime 2 years Total Power (CBE) 875 W Aperture 30 cm Delta-V 215 m/s Delta 2925H 3-m

17 EPIC-LC Systematics Mitigation Strategy Systematic Description Goal Mitigation Polarized main beam effects Δ Beam Size FWHM E FWHM H < 4 x 10-5 Δ Gain G E G H < 10-4 HWP in front of telescope Δ Beam Offset Point E Point H < 0.14 Measure and subtract Δ Ellipticity e E e H < 6 x 10-6 Δ Rotation E, H not orthogonal < 4 Scan crossings Pixel rotation E, H rotated < 2.4 Optical Cross-Pol Birefringence < 10-4 Orbit-modulated dipole Satellite Pointing Q, U offset < 12" Gyro + tracker Scan Synchronous Signals Far Sidelobes Diffraction, scattering Refractor + baffle Thermal Variations Changing sun angle < 1nK CMB Thermal design Magnetic Pickup Detector susceptibility Shielding Thermal Stability 40 K Baffle 5 mk/ Hz Varying optical power 2 K Optics 500 uk/ Hz Temperature control 0.1 K Focal Plane Varying thermal signal 200 nk/ Hz Other 1/f noise Detector, readout drift 16 mhz Stabilize focal plane Passband mismatch Variation in filters Δν/ν < 10-4 Measure Demonstrated in space; will be demonstrated by Planck Space required Demonstrated in suborbital experiments Planned sub-orbital demonstration

18 Wide-Field Refracting Optics EPIC Projected Bands and Sensitivities Absorbing Baffle (40 K) Half-Wave Plate (2 K) Aperture Stop (2 K) 30 cm Telescope [#] Total Freq [GHz] 30 / / 300 FWHM [arcmin] 155 / / 16 Ndet [#] 8 / / Measured BICEP1 Sidelobe Response NET/band [uk s] 28 / / ~20% polarized Polyethylene Lenses (2 K) Telecentric Focus Focal Plane Bolometer Array (100 mk)

19 Scan Strategy Scan Coverage Precession (~1 rph) 1 minute Sun-Spacecraft Axis Downlink To Earth 3 minutes 1 hour

20 Scan Strategy 1 Day Maps 55 Precession (~1 rph) 45 Sun-Spacecraft Axis Spatial Coverage Downlink To Earth Angular Uniformity More than half the sky in a single day

21 Redundant & Uniform Scan Coverage N-hits (1-day) Angular Uniformity* (6-months) Planck WMAP EPIC *<cos 2β> 2 + <sin 2β> 2 0 1

22 Mission Design Options: Large Configuration Main Features Passively Cooled Gregorian Frequency Bands GHz Orbit L2 Halo Resolution 5 at 90 GHz Inflow Data Rate 2.3 Mbps Detectors 1520 TES bolos Total Mass (CBE) 3500 kg Design Lifetime 4+ years Total Power (CBE) 1030 W Aperture 2.8 m Delta-V 215 m/s 3 m Primary Lyot stop (HWP) Bipod Support Ring 40 K Secondary 155 K 293 K 85 K Inner Radiation Shield Lenses (2-4 K) Focal Plane (100 mk) 3-Axis Zero-Momentum Spacecraft Solar Panels Gimballed Antenna

23 Mission Design Options: Large Configuration Main Features Frequency Bands GHz Orbit L2 Halo Resolution 5 at 90 GHz Inflow Data Rate 2.3 Mbps Detectors 1520 TES bolos Total Mass (CBE) 3500 kg Design Lifetime 4+ years Total Power (CBE) 1030 W Aperture 2.8 m Delta-V 215 m/s 3 m Bipod Support Ring 40 K Rad. Shields 3-Stage V-Groove Inner Radiation Shield Cryocooler 155 K 293 K 85 K Atlas 5-m shroud 3-Axis Zero-Momentum Spacecraft Solar Panels Gimballed Antenna

24 Why Design an Intermediate Mission? 3.5 m A Happy Medium Maximize science with 1-2 m aperture Minimize cost (aka mass) Choose technology carefully 13 m 1300 kg 3500 kg -Targeted Science + Cost + High-TRL approach + Broad Science -Cost - TRL push

25 Intermediate Mission Design Secondary Primary 2 K Aperture Stop 40 K Optics Box Focal Plane Deployed sunshields Fixed V-Grooves Cryocooler compressors New Design Features Crossed-Dragone reflector: no broad-band lenses 2-4 K mechanical cooler: less mass & extended life Forward-canted sunshields: shorter, smaller deployable Atlas 4-m shroud

26 Intermediate Mission Optics Crossed Dragone Telescope GHz GHz Strehl Ratio* GHz 150 GHz 50 GHz m No Lyot stop Telecentric designs exist Huge 18 x 38 FOV! ~10x more AΩ than used by EPIC-large or EPIC-small

27 Intermediate Mission Optics Crossed Dragone Telescope GHz GHz Strehl Ratio* GHz 150 GHz 50 GHz 1.4 m No Lyot stop Telecentric designs exist Huge 18 x 38 FOV! ~10x more AΩ than used by EPIC-large or EPIC-small

28 Focal Plane Design Considerations Available FOV Freq [GHz] Nfeeds [#] new band!? Total: 3.25fλ pixels Still ~2x more detectors than EPIC-large 10 K 2 K 400 mk 100 mk 130 cm

29 Add 850 GHz Band for Galactic Science? coverage map for σ(p) 0.3 % Orion Molecular Cloud, 850 GHz outflow filaments embedded star clusters Planck 5 EPIC 4K, 1 EPIC 40K, 5 mapping polarization over wider fields photodissociation region 5 res. 1 res. improved resolution magnetic field structure of clouds at formation, dispersal Andromeda Galaxy at 1 resolution (Gordon et al. 2006) magnetic field structure of nearby galaxies

30 Challenges: Optics Challenge Main beam control Sidelobe control EPIC Approaches Small aperture + waveplate Large aperture + control & measure Lyot stop & lenses Cold stop Issues Lack detailed model, untested Untested Broadband coatings, untested Pixel size packing vs. control EPIC-small 30 cm refractor EPIC-medium 1.5 m Crossed Dragone EPIC-large 3 m Gregorian Dragone

31 Challenges: Detectors Challenge Array uniformity Base temperature Polarization analysis EPIC Approach TES or MKID 100 mk Two detectors per pixel Issues First focal planes coming into use Optical efficiency & noise important New detectors higher temperature? Simultaneous Q&U? Antenna Coupling Direct Detectors Planar Lens-Coupled Feed-Coupled TES Bolometer Kinetic Inductance Detector

32 Challenges: Readouts Challenge Formats Noise stability Focal plane packaging Systems issues - magnetic shielding - EMI/EMC - microphonics EPIC Approach 2k-5k detector in multiple bands Assume focal plane stable Allocate mass and volume Allocate mass and volume Issues Need uniformity, stability & immunity Build stability into the readouts Large multi-color focal planes - space efficiency - modularity Build immunity into the readouts Time Domain SQUID Frequency Domain SQUID FD HEMT + KID SCUBA2 BICEP2 SPT-SZ EBEX CSO-CAM

33 Challenges: Coolers Challenge 100 mk cooler 2-4 K cryo-cooler EPIC Approach 1 uw dissipation + parastics Need 400 mk intercept Continuous is highly desirable Required stability ~Planck Mass advantage over cryostat Issues Several options: cadr, CCDR 2 K coolers need development Interactions with detectors? System ground testing Cryocooler Continuous ADR Planck OCDR

34 Conclusions Sensitivity and Band Coverage Important - EPIC scoped for maximum performance - Until we know otherwise, don t descope How Big an Aperture? - Depends on the science case - We are now developing a 1-2 m concept Technology Readiness - We have the capability for a very capable mission today - Technology advances improve the science performance - New technologies: new capabilities, new systems issues

35 Backup Slides

36 Alternate Intermediate Mission Design Primary Secondary 2 K Aperture Stop Focal Plane 40 K Optics Box Deployed Sunshields Fixed V-Grooves Cryocooler compressors New Design Features Crossed-Dragone reflector: no broad-band lenses 2-4 K mechanical cooler: less mass & extended life Forward-canted sunshields: shorter, smaller deployable Atlas 4-m shroud

37 Sunshield Deployment Sequence

38 Sunshield Deployment Sequence

39 Sunshield Deployment Sequence

40 Sunshield Deployment Sequence

41 Sunshield Deployment Sequence

42 Sunshield Deployment Sequence

43 T 0 = 250 mk for the Inflation Probe?