polar-1 and the polar array
DESCRIPTION
POLAR-1 and the POLAR Array. Chao-Lin Kuo Physics Department & SLAC PPA, Stanford University Kavli Institute for Particle Astrophysics and Cosmology. Collaborators. Harvard John Kovac Minnesota Clem Pryke. Stanford Chao-Lin Kuo Keith Thompson Ki Won Yoon Kimmy Wu - PowerPoint PPT PresentationTRANSCRIPT
Chao-Lin KuoChao-Lin KuoPhysics Department & SLAC PPA, Stanford UniversityPhysics Department & SLAC PPA, Stanford University
Kavli Institute for Particle Astrophysics and CosmologyKavli Institute for Particle Astrophysics and Cosmology
POLAR-1 and the POLAR ArrayPOLAR-1 and the POLAR Array
Collaborators Collaborators StanfordStanford
Chao-Lin KuoChao-Lin Kuo Keith ThompsonKeith Thompson Ki Won Yoon Ki Won Yoon Kimmy WuKimmy Wu Sarah Church Sarah Church
Caltech/JPLCaltech/JPL Jamie Bock Jamie Bock Roger O’BrientRoger O’Brient Howard Hui Howard Hui Marc RunyanMarc Runyan Hien NguyenHien Nguyen
UBCUBC Mark HalpernMark Halpern
NISTNIST Kent IrwinKent Irwin Gene HiltonGene Hilton
HarvardHarvard John Kovac John Kovac
MinnesotaMinnesota Clem Pryke Clem Pryke
C. L. Kuo POLAR ArraySupports from NSF-OPP-MRI
The South Pole Station; 2015?
The POLAR Array: * array of multiple mid-size reflectors for CMB polarization* (a few) arcminte resolution * multi-frequency (distribution TBD)* 10% the survey speed of CMBPOL * ~ 12 kW power, 0.1 TB/day data per element
Image:C. Sheehy & K. Thompson
Unlensed pure E-mode
C. L. Kuo POLAR Array
Lensing field
C. L. Kuo POLAR Array
Lensed B-mode
WH TengC. L. Kuo POLAR Array
Lensing Lensing BB-mode measurements as of April 2011 -mode measurements as of April 2011
• QUaD/BICEP (50~100 detectors) still miss the B-polarization by ~ 2 orders of magnitude.
•To perform high S/N imaging of lensing B-polarization, one must increase the survey speed by 102.
H. Chiang
C. L. Kuo POLAR Array
Lensing Lensing BB-polarization is a LSS experiment-polarization is a LSS experiment Deep polarization measurements can significantly improve Deep polarization measurements can significantly improve
Planck+WFIRST/Euclid’sPlanck+WFIRST/Euclid’s constraints on {w, constraints on {w, kk, ∑m, ∑m} etc., } etc., If one assumes a prior of If one assumes a prior of
ww00= -1, w= -1, waa=0, =0, k k <10<10-4 -4 → lensing → lensing BB provides a constraint on ∑m provides a constraint on ∑m<0.04 eV <0.04 eV
This will eitherThis will either DetectDetect a neutrino mass a neutrino mass Rule out inverted hierarchyRule out inverted hierarchy
Lesgourgues and PastorPhysics Reports, 2006
alsoAstro-2010 Panel Reports
C. L. Kuo POLAR Array
Neutrino from CosmologyNeutrino from CosmologyAbazajian et. al. 2011
(primarily for T)
It is possible to “undo” the lensing (delensing)It is possible to “undo” the lensing (delensing)
E-map B-map
(E,B)
Expected B-map from lensing
reconstructionsubtract Delensed
B-map
• The lensing potential can be reconstructed to predict the expected B-mode from lensing• This procedure is noise limited in principle• With ~1 K-arcmin noise (target noise level for POLAR Array deep survey), a factorof 4 reduction in lensing B-mode contamination
Hu & OkamotaHirata& Seljak
C. L. Kuo POLAR Array
Two Surveys with the Two Surveys with the POLAR ArrayPOLAR Array
• The Deep Survey • 400 square degrees ; 1 K-arcmin• Deep search of Primordial B-mode with de-lensing (4×)• Possible to reach well below r~0.01 , depending on dust foreground
• The Wide Survey• Tens of thousands of square degrees ; 6-10 K-arcmin• Neutrino mass (~0.06 eV) • ns, k, dark energy from lensing and EE/TE
• Precise measurements of r or nt (in the event that r is large)
(funded) 1.6m 2000×2 400
POLAR-1, a technological/scientific pathfinderPOLAR-1, a technological/scientific pathfinder
• Feeding 2,000 detector pairs (2.1 F) with a 1.6m telescope @150 GHz
• 5% spillover scattered toward the cold sky (15 K) – actively cooling avoided
• Twenty 4” silicon detector tiles (BICEP-2 has 4, Keck-2011 has 12)
• Large-aperture infrared filters (50cm) and vacuum window (60cm)
• Mitigation of beam/polarization systematics
• POLAR-1 will reach the survey depth of CMBPOL in 1% of the sky
High order-correctedcrossed-Dragone optics
Scatterer (K. Yoon)
Large, flat, telecen. focal plane
Antenna developmentAntenna development
• Lead: JPL / Caltech
• Planar antennas in BICEP2/Keck have
uniform excitation & -15dB sidelobe
• Planar antenna with tapered excitation
reduces spillover power
• Tapered antennas with 2.5, 2.1, 1.7 F
being developed
• Testing throughout 2011
R. O’Brient
C. L. Kuo POLAR Array
POLAR-1 focal plane camera
BICEP-2Focal plane, 512 detectors(fielded 2009)
Keck Array = BICEP-2 x 3(5)(fielded 2010/2011)
POLAR-1 Focal plane ~4,000 detectors (2,000 pairs) • Modular tile design• 21 tiles with POLAR-1’s crossed-Dragone• A technology pathfinder for POLAR Array
• 33,600 wirebonds per receiver for POLAR?• Or, should we look for a monolithic technology? • Bump bonding hybridization ?
Caltech: M. Runyan
C. L. Kuo POLAR Array
POLAR-1 experimentPOLAR-1 experiment
K. Thompson C. L. Kuo POLAR Array
POLAR Array OptimizationPOLAR Array Optimization
• What is the appropriate aperture/resolution?What is the appropriate aperture/resolution?
• What is the appropriate sky coverage for each survey? What is the appropriate sky coverage for each survey?
• What is the appropriate frequency coverage? What is the appropriate frequency coverage?
C. L. Kuo POLAR Array
Aperture vs # of elementsAperture vs # of elements For a given project cost – POLAR Array can have more For a given project cost – POLAR Array can have more
smaller (2m) elements or fewer larger (5m) elementssmaller (2m) elements or fewer larger (5m) elements Assuming the cost of the telescope scales as DAssuming the cost of the telescope scales as D2.52.5 power and a power and a
fixed cost per receiver, we compare these options:fixed cost per receiver, we compare these options:
These are all assumed to be crossed-Dragone systems (~2,000 These are all assumed to be crossed-Dragone systems (~2,000 TES pairs each), at 150 GHzTES pairs each), at 150 GHz
Aperture Dia. (m)
Beam (arcmin) Approx. unit cost ($m)
# of tel. w/ fixed budget
2 5 2 10
3 3.3 3.8 5
4 2.5 6.7 3
5 2 10.9 2
C. L. Kuo POLAR Array
Survey assumptions Survey assumptions 450uK∙√s ; 20,000 TES pairs @ 150 GHz with 75% yield; 450uK∙√s ; 20,000 TES pairs @ 150 GHz with 75% yield;
observing for 3×10observing for 3×1077 s (30% efficiency for 3 yrs) s (30% efficiency for 3 yrs)
Deep surveyDeep survey
10% time from the 150 GHz channel10% time from the 150 GHz channel
Assume that the foreground channels reach the same sensitivity Assume that the foreground channels reach the same sensitivity
Wide survey Wide survey
Foreground unlikely an issue for lensing science Foreground unlikely an issue for lensing science
““Throughput” might loose to foreground channels for the deep surveyThroughput” might loose to foreground channels for the deep survey
Can be reconfigured if a tensor mode is detected Can be reconfigured if a tensor mode is detected
C. L. Kuo POLAR Array
Neutrino massNeutrino mass
Kimmy Wu, 2011Fraction of sky to cover
uncertainty in neutrino mass
Planck only(M)=0.46 eV
SPTPOL proposed survey
C. L. Kuo POLAR Array
TE/EE, or lensing?TE/EE, or lensing?
Kimmy Wu, 2011Fraction of sky to cover
uncertainty in neutrino mass
Planck only(M)=0.46 eV
Lensing from POLAR ArrayTT/TE/EE from Planck
TE/EE/Lensing from POLAR ArrayTT from Planck, also TE/EE in 1-fsky
C. L. Kuo POLAR Array
Kimmy Wu, 2011Fraction of sky to cover
uncertainty in neutrino mass
Planck only(M)=0.46 eV
2500 sq deg@ 25uK (P) (1’)
Neutrino mass, with degraded survey speedNeutrino mass, with degraded survey speed
C. L. Kuo POLAR Array
Scalar spectral indexScalar spectral index
Kimmy Wu, 2011Fraction of sky to cover
uncertainty in scalar index ns
Planck w/ H0
(ns)=0.0072
C. L. Kuo POLAR Array
Spatial curvatureSpatial curvature
Kimmy Wu, 2011Fraction of sky to cover
uncertainty in curvaturek
Planck w/ H0
(k)=0.0115
C. L. Kuo POLAR Array
Sensitivity to tensor modeSensitivity to tensor mode
WH. Teng
C. L. Kuo POLAR Array
Sensitivity to tensor modeSensitivity to tensor mode
WH. Teng
C. L. Kuo POLAR Array
Sensitivity to tensor modeSensitivity to tensor mode
WH. Teng
Foreground ignored, otherwise optimal width will shift further to smaller coverage (~10-20 deg)C. L. Kuo POLAR Array
If If rr=0.1, 1-=0.1, 1- uncertainty on ( uncertainty on (r,nr,ntt) ?) ?
C. L. Kuo POLAR Array
C. L. Kuo POLAR Array
Foregrounds
Dunkley et al., 2009CMBPOL Foreground study(1–2% dust polarization)
dust(model)
synchrotron(model)
At l=80-120for r =0.01
Lines indicate different sky coverage: full-sky, |b| > 10, |b| > 30, |b| > 50, and a circular patch of radius 10 in the cleanest part of the sky
C. L. Kuo POLAR Array
ForegroundForeground
Dunkley et al. 2009
Remaining questions on defining the Remaining questions on defining the POLAR ArrayPOLAR Array
Frequency distribution Frequency distribution Sky coverage and lowest elevation Sky coverage and lowest elevation Cross correlation with optical surveys Cross correlation with optical surveys Technology Technology ……..
C. L. Kuo POLAR Array
ConclusionConclusion
POLAR Array attempts to extract most of the science with POLAR Array attempts to extract most of the science with
lensing fro the ground (speed ~ 10% of CMBPOL) lensing fro the ground (speed ~ 10% of CMBPOL)
Inflation energy scale (Inflation energy scale (rr<0.01)<0.01)
Neutrino mass (∑mNeutrino mass (∑m<0.06 eV)<0.06 eV)
Significant improvements over Planck on spatial curvature, dark Significant improvements over Planck on spatial curvature, dark
energy, spectral index energy, spectral index
POLAR-1, a pathfinder for POLAR Array is under POLAR-1, a pathfinder for POLAR Array is under
construction – first light in 2012/13construction – first light in 2012/13
C. L. Kuo POLAR Array
The South Pole Station; 2015?
Image:C. Sheehy & K. Thompson
Thank you !Thank you !
The POLAR Array: * array of multiple mid-size reflectors for CMB polarization* (a few) arcminte resolution * multi-frequency (distribution TBD)* 10% the survey speed of CMBPOL * ~ 1.2 kW power, 0.1 TB/day data per element
Backup slidesBackup slides
Neutrino & the LSSNeutrino & the LSS
Tegmark 2005
neutrino mass @ 1eV structures are damped by 2×
B-mode is B-mode is forbiddenforbidden for density perturbations for density perturbations(Seljak& Zaldarriaga, 1997; Kamionkowski et al., 1997)
e-observer
for an arbitrary circleon the sky
point source
Lensing can generate B-modeLensing can generate B-mode(Zaldarriaga & Seljak, 1999)
e-observer
for an arbitrary circleon the sky
point source
B-mode theoremB-mode theorem
Polarization fields can be linearly Polarization fields can be linearly
decomposed to E and B modedecomposed to E and B mode
Linear, scalar perturbation cannot Linear, scalar perturbation cannot
generate B-mode polarizations generate B-mode polarizations
No cosmic varianceNo cosmic variance
(Seljak & Zaldarriaga; Kamionkowski et al, (Seljak & Zaldarriaga; Kamionkowski et al,
1997)1997)
E
B