Title Here

Experimental Probe of Inflationary Cosmology (EPIC)

Jamie BockJPL / Caltech

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

The EPIC ConsortiumCaltech/IPAC Charles Beichman Sunil Golwala Marc Kamionkowski Andrew Lange 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

JPL 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 Ron Ross Celeste Satter Mike Seiffert Hemali Vyas Brett Williams

UC Irvine Alex Amblard Asantha Cooray Manoj Kaplinghat

U Minnesota Shaul Hanany Tomotake Matsumura Michael Milligan

NIST Kent Irwin

UC San Diego Brian Keating Tom Renbarger

Stanford Sarah Church

Swales Aerospace Dustin Crumb

TC Technology Terry Cafferty

USC Aluizio Prata

Title HereUS Activities and Opportunities

NASA funded 3 mission studies for the Einstein “Inflation Probe” in 2003• Envisioned as $350-$500M mission, launch 2010 & every 3 years• Since 2003 there have been some programmatic changes at NASA…• Oral reports were given at NASA HQ this month• Written reports are still being drafted

Task Force For CMB Research (Weiss Committee) in 2005• Programmatic and technical roadmap to a 2018 launch for US agencies• Two mission options described• Sets mission guidelines: r = 0.01 is science goal

NRC panel to recommend first Beyond Einstein mission to NASA• First Beyond Einstein mission funding is to turn on 2008-9• CMBPOL, Con-X, LISA, JDEM (aka SNAP), and Black Hole Finder• Recommendation based on “scientific merit and technical readiness”• NRC also to recommend areas for technology funding for next 4 BE missions• Three CMBPOL study teams will organize a single presentation to NRC

MIDEX call expected in October 2007• Expected cap $220 - $260M including launch vehicle and 30 % cost reserve• Launch 2013 - 2015• International participation in MIDEX’s limited in the past (~30 %)• Unknown if NASA would change the rules for this AO... probably unlikely

Title HereTwo Mission Scenarios for CMBPOL

Gravitational-Wave BB Polarization Clear Justification for Space Mission - Large angular scales required

Modest Mission Parameters - Enough sensitivity to hit lensing limit - Angular resolution to probe ℓ = 100 - Broad frequency coverage

High-ℓ Science Lensing BB signal - How deeply can we remove lensing? - Will foregrounds limit us first? - How much more science do we get? - Do we need to go to space for this?

EE power spectrum to cosmic variance - Much will be done from the ground

T

E

B

B

Scalars

IGWs

r = 0.01

Dust

Synchr = 0.3

Cosmic Shear

Title Here

FUTUREPLANNEDACTIVE

EPIC is a Scan-Imaging Polarimeter

Scan detectors across sky to build CMB map Simple technique. Established history in CMB. Scaling to higher sensitivity → Only need better arrays Adapt this technique for precision polarimetry

Two mission concepts* Low Cost: High-TRL, low-resolution, sufficient capability Comprehensive Science: Larger aperture, new arrays

*See Weiss Committee TFCR Report: astro-ph 0604101

Planck

Boomerang

BICEP

QUaD

Polarbear

Maxipol

PAST

EBEX Spider

Title Here

Spin A

xis

(~1

rpm

)

Sun-Spacecraft Axis (~1 rph)

Op

tica

l Axi

s

Sun Earth

Moon

SE L2

45°55°

Orbit

Why Space?

- All-Sky Coverage - High Sensitivity - Systematic Error Control - Broad Frequency Coverage

Title Here

Title HereScan Strategy

Sun-Spacecraft Axis

45˚

DownlinkTo Earth

Precession(~1 rph)

55˚

1 m

inu

te3

min

ute

s1

ho

ur

Scan Coverage

Title HereScan Strategy

Sun-Spacecraft Axis

45˚

DownlinkTo Earth

Precession(~1 rph)

55˚

1 Day Maps

Spatial Coverage

Angular Uniformity

More than half the sky in a single day!

Title HereRedundant & Uniform Scan Coverage

Planck

WMAP

EPIC

N-hits (1-day) Angular Uniformity* (6-months)

*<cos 2>2 + <sin 2>2 0 1

Title Here

DeployedSunshield

Solar Panels

Liquid Helium Cryostat (450 ℓ)

Six 30 cm Telescopes

CommercialSpacecraft

Toroidal-Beam Antenna

Half-Wave Plate

Absorbing Forebaffle

2 K Refracting Optics

100 mK Focal Plane Array

3-Stage V-Groove Radiator8 m

Delta 2925H 3-m

EPIC Low Cost Mission Architecture

155 K

100 K

40 K

295 K

30/40 GHz 60 GHz 2 x 90 GHz 135 GHz200/300 GHz

Title HereLow-Cost Sunshield Deployment Sequence

Title HereLow-Cost Sunshield Deployment Sequence

Title HereLow-Cost Sunshield Deployment Sequence

Title HereLow-Cost Sunshield Deployment Sequence

Title HereLow-Cost Sunshield Deployment Sequence

Title HereLow-Cost Sunshield Deployment Sequence

Title HereComprehensive Science Mission Architecture

Atlas V 551

LHe Dewaror Cryocooler

3-Stage SunshieldWrap-Rib Deployment

3-Axis S/C

3-Stage V-Groove

Passively Cooled Mirrors

40 K

293 K

155 K

85 K

Gimballed AntennaSolar Panels

20 m

2.8 m

Receiver & Lenses

Title HereSensitivity with Existing Detector Arrays

AbsorbingBaffle (40 K)

Half-WavePlate (2 K)

PolyethyleneLenses (2 K)

TelecentricFocus

ApertureStop (2 K)

Focal Plane Bolometer Array

(100 mK)

Freq[GHz]

FWHM[arcmin]

NTD Ge Bolometers Planck

#[det’s]

NET/det*[Ks]

NET*[Ks]

NET/det†

[Ks]

30 155 8 69 24.5

40 116 54 60 8.2

60 77 128 49 4.4

90 52 256 42 2.6 102

135 34 256 38 2.4 83

200 23 64 41 5.1 134

300 16 64 95 11.8 404

Total 830 1.5

*De

sig

n S

ensi

tivity

†G

oal S

ensi

tivity

Instrument Technology NET [Ks] Value

HFI100 – 850 GHz

NTD Ge

Bolometer

20.3 Design Goal

< 16.7 Measured

LFI30 – 70 GHz

HEMT 68.9 Req’t

EPIC Projected Bands and Sensitivities

Planck Projected Sensitivities

Note modest detector improvement over Planck dueto relaxed time constant specification & 2 K optics

30 cm

Title HereNTD Bolometers for Planck & Herschel

SPIRE Low-power JFETs

143 GHz Spider-web Bolometer

Herschel/SPIRE Bolometer Array

NTD Germanium

Planck/HFI focal plane (52 bolometers)

Title Here

8 mm

Antenna-Coupled Bolometers for EPIC

Single Pixel – Dual Pol at 150 GHz (JPL/CIT)

Advantages

Small active volume.. 30 – 300 GHz operationBeam collimation…... Eliminates discrete feeds

Reduced focal plane massIntrinsic filters…….... No discrete components

Y-polarizationX-polarization

High OpticalEfficiency!

Measured Spectral Response

Kuo et al. SPIE 2006

Measured Beam Patterns

Title Here

New technologies bring enhanced capabilities…

Antenna-Coupled TES / MKID detectors Higher sensitivity, less mass & power Continuously rotating waveplate Better beam control Continuous ADR Less mass, no interruptions

…but we have the technology to do this mission today

Low-Cost Mission: High Technology Readiness

Technology TRL Heritage

Focal Plane Arrays (NTD Ge bolometers)

NTD thermistors and readouts

Antennas

8

4

Planck & Herschel

Wide-Field Refractor 6 BICEP

Waveplate (stepped every 24 hours)

Optical configuration

Cryogenic stepper drive

6

9

SCUBA, HERTZ, etc.

Spitzer

LHe Cryostat 9 Spitzer, ISO, Herschel

Sub-K Cooler: Single-shot ADR 9 ASTRO-E2 (single-shot)

Deployable Sunshield 4-5 TRL=9 components

Toroidal-Beam Downlink Antenna 4-5 TRL=9 components

Title HereTES Bolometer Arrays

Freq. Domain (UCB/LBNL) Time Domain (NIST)

SQUID Multiplexing

Antenna-Coupled TES Bolometers (UCB/LBNL)SCUBA2 Focal Plane (10,000 TES Bolometers)

Advantages

Multiplexing……. Larger array formatsHigher sensitivityFewer wires to 100 mKLow cryogenic power disp.

Faster response... Useful for larger aperture

Title HereLow-Cost Mission Focal Plane Options

TES Bolometer Option

Freq[GHz]

FWHM

[′]Nbol3

[#]

Required Sensitivity1 Design Sensitivity2

NET4 [Ks] T-5

[K ′]Tpix6

[nK]NET4 [Ks] T-5

[K ′]Tpix6

[nK]bolo band bolo band

30 155 8 87 30.8 66.7 560 62 22 33.4 280

40 116 54 77 10.4 22.7 190 54 7.4 11.3 95

60 77 128 66 5.8 12.7 107 47 4.1 6.3 53

90 52 512 59 2.6 5.6 47 41 1.8 2.8 24

135 34 512 59 2.6 5.7 48 42 1.9 2.8 24

200 23 576 72 3.0 6.5 55 51 2.1 3.2 27

300 16 576 145 6.0 13.0 110 100 4.2 6.5 55

Total7 2366 1.5 3.2 27 1.0 1.6 13

NTD Bolometer Option

Freq[GHz]

FWHM

[′]Nbol3

[#]

Required Sensitivity1 Design Sensitivity2

NET4 [Ks] T-5

[K ′]Tpix6

[nK]NET4 [Ks] T-5

[K ′]Tpix6

[nK]bolo band bolo band

30 155 8 98 34.6 106 630 69 24.5 53.1 315

40 116 54 85 11.5 35.4 210 60 8.2 17.7 105

60 77 128 70 6.2 18.9 110 49 4.4 9.5 56

90 52 256 59 3.7 11.3 67 42 2.6 5.6 34

135 34 256 53 3.3 10.2 61 38 2.4 5.1 30

200 23 64 58 7.2 22.1 130 41 5.1 11.0 66

300 16 64 135 16.7 51.4 310 95 11.8 25.7 150

Total7 830 2.1 6.5 39 1.5 3.3 19

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Input AssumptionsFractional bandwidth / = 30 % Optical efficiency = 40 %Focal plane temperature = 100 mK Optics temperature = 2 K, with 10 % couplingWaveplate temperature = 20 K, with 2 % coupling Baffle at 40 K with 0.3 % coupling (measured)Psat/Q = 5 for TES bolometers G0 = 10 Q / T0 for NTD bolometers

Title Here

Instrument Design Goal Instrument Requirement

Suppress raw systematic effect below statistical noise level

Suppress systematic errorsbelow r = 0.01 after correction

Systematic Effect Design Goal Mitigations Heritage

Main

Be

am E

ffects

Beamsize 1e-4

• Refracting telescope

• Waveplate before telescope

• Scan crossings & CMB dipole

BICEP†

SPIDER‡

---

Gain 8e-5

Beam Offset 5e-5Ellipticity 1e-3

Pol. Beam Rot’n 3e-4

Polarized Sidelobes 1 nKrms • Refractor + baffle BICEP*

1/f Noise 16 mHz

• Drift-scanned NTD bolometers

• Or TES + modulator

• Scan crossings

BOOMERANG*

EBEX/SPIDER/POLARBEAR‡

---

Scan-Synch Signals 1 nKrms • Scan redundancy ---

Optics Temp. Stability10 Krms s/s300 K/Hz

• Dual analyzers

• Temperature monitoring & control of all critical stages

Planck*

Planck*Focal PlaneTemp. Stability

3 nKrms s/s150 nK/Hz * = Already demonstrated to EPIC requirement

† = Proof of operation but needs improvement‡ = Planned demonstration to EPIC requirement

Systematic Error Mitigation Strategy

Title Here

BICEP

Wide-Field Refracting Optics

• Wide unaberrated FOV

• Excellent main beams

• Telecentric focus

• Waveplate = first optic

• Ultra-low sidelobes

• Field tested in BICEP

Title HereWide-Field Refracting Optics

Freq Band[GHz]

FWHM[arcmin]

FOV*[deg]

30 / 40 155 / 116 28

60 77 25

90 52 22

135 34 19

200 / 300 23 / 16 17

*Strehl ratio > 0.95

BICEP

Title HerePolarization Systematics: Main Beams

Differential FWHM

Differential Beam Offset Differential Ellipticity

Differential Gain, Rotation

Main Beam Instrumental Polarization Effects

Calculation- Difference PSB beam pairs- Parameterize main beam effects- Convolve w/ scan pattern- Calculate resulting power spectrum

Caveats- Calculation is conservative → single pixel- We can always apply post facto correction- Waveplate eliminates these effects

Title HereMain Beam Systematic Errors - Requirement

Title HereMain Beam Systematic Errors - Goal

Title HereMain Beam Properties at 135 GHz

PSF

Systematic Goal* Req’t* Calc† Meas‡

Gain (g1-g2)/g 8e-5 3e-4 2e-4 < 5e-3

Beam Size (1-2)/ 1e-4 3e-4 1e-4 < 2e-3

Beam Offset /2 5e-5 2e-4 4e-6 6e-3

Ellipticity (e1-e2)/2 1e-3 3e-3 1e-4 < 1e-3

Pol. Rotation 3e-4 1e-3 5e-6 8e-4 *Goal: Suppress effect without correction below noise**Req’t: Suppress effect with correction below r = 0.01 †Calc: Worst performance over the FOV at 135 GHz‡Meas: Median value measured in BICEP receiver

Difference BeamPSF Difference Beam

Performance at FOV Center

Performance at FOV Edge

Title HereMeasured Beam Offsets in BICEP

Title Here

BICEP Measurements Sky at 100 GHz

Levels below 3 nK for most of the sky!

Far-Sidelobe Performance

~ 20% polarized

3nK

10

100

30

1 K

10

100

1e3

1e4

1e5

Sidelobe Map at 100 GHz

Title HereForegrounds - What We Know Today

75% of sky 75% of sky

2% patch 2% patch

3. Results• Removal gives a modest sensitivity loss• Better sensitivity → better subtraction (model is linear)

4. Conclusion: FGs Look Manageable!• Preliminary. We might find a new component tomorrow• We don’t know where a linear model fails

Sensitivity per 14′ Pixel

EPICWMAP-8Planck

Case Required Sens. Design Sens.

No foregrounds 35 12

s and d fixed 50 17

s and d fitted

in 30˚ patches55 18

s and d fitted

in 30˚ patches70 22

ComponentSpectrum

(I )Amplitude (Stokes I)

Pol. fraction

CMB =0 70K 1%

Synchrotron =-3.0 40K @ 23GHz 10%

Free-free =-2.15 20K @ 23GHz 1%

Thermal DustFDS model 8

(~+1.7)10K @ 94GHz 5%

Spinning Dust DL98 (WNM) 50K @ 23GHz 2%

nKCMB in 2˚ pixels

2. Multi-band Removal• Fit only synch & thermal dust• Fit components spectrally• Let indicies float spatially

Eriksen et al. 2006

Input Sky Model

Resulting Sensitivity After Subtraction

1. Input Sky Model• All components we know about today

Title HereConclusions

Exciting CMB science in the post-Planck era § Clear role for gravitational-wave polarization science in space § High-ℓ science compelling but need for space is less robust

Imaging polarimeter approach § Technically and scientifically feasible § Simple technique, established history. § Simple scaling to higher sensitivity: improve the focal plane. § Design in extensive control of systematics from the beginning § Low-Cost option → meets Weiss Committee guidelines for GW science § Comprehensive Science option → more capable, more science, more $

Foregrounds § What we know today about polarized foreground shows they can be subtracted below r = 0.01

Technologies § We can build a very capable mission today with existing technology § New technologies will improve the mission & reduce technical risk