The South Pole Telescope

Erik Leitch University of Chicago

SPT Collaboration

Summary

•  Site Description

•  Motivation for the SPT

•  SPT-SZ

•  SPTpol

•  SPT-3G

South Pole Site

Wintertime median of 0.25 mm precipitable water (c.f. 25 mm worldwide, and 1 mm at Chajnantor) 30 x less atmospheric fluctuation power than Chajnantor

South Pole Logistics South Pole Infrastructure

LC-130 limited to 12,000 kg load In 2007, we transported 660,000 lbs. of material to build SPT Over 33 C-130 flights that season alone (Over 5000 M27x150mm bolts in the telescope structure!)

And Limitations…

South Pole Logistics A Brief History of CMB at the South Pole

2000

DASI

2001-2005

ACBAR

2005-2009

QUAD

BICEP

2002

SPT

Cosmological Parameters

DASI (2001)

WMAP9

Structure Formation

Abundance of clusters is sensitive to the dark energy equation of state, w = p / 𝝆

(If dark energy due to a cosmological constant then w = -1)!

Depends on: Matter Power Spectrum, 𝝈8 Growth Rate of Structure, D(z)

Depends on: Rate of Expansion, H(z)

The SZ Effect

Spectral distortion as CMB photons pass through the hot intracluster medium SZ brightness is independent of distance (depends only on integrated pressure ~ or roughly, mass)

The SPT Telescope

SPT 10-meter Gregorian, with < 20-micron rms surface accuracy No chopper; telescope can scan at 4 deg/sec, 2 deg/sec2 acceleration SPT-SZ: operated at three frequencies:

95, 150 and 220 GHz (1.3 - 3 mm) Diffraction limited beam of 1’ at the highest frequency provides good match to typical cluster scale

The SPT Telescope

SPT Focal Plane

Horn-coupled spider-web bolometers!

TES thermometers!

960 detectors, instantaneous FOV ~ 1 degree

Wedges at 100, 150 and 220 GHz!

Cooled by pulse-tube refrigerator and a 3-stage He sorption refrigerator to 250 mK!

Final survey depths of:!-  100 GHz: < 40 uKCMB-arcmin !-  150 GHz: < 18 uKCMB-arcmin!-  220 GHz: < 80 uKCMB-arcmin!

SPT Survey 2007-2011

SPT Results

SPT relative to WMAP:!!SPT has 13x smaller beam (13’ vs 1’)!!SPT is 17x deeper (300 uK-arcmin vs 18 uK-arcmin)!

First SZ Detected Clusters

First blind detections of SZ clusters (from early 40 sq deg obs) SNR > 5-sigma at 150 GHz Consistent with SZ spectrum

Staniszewski et al: arXiv:0810.1578

Cluster Catalog Catalog from first 720 sq: 224 clusters detected with SNR > 4.5 Complete above M500

> 5x1014 M at z > 0.6 2x1014 < M500 < 8.4x1014 M "(currently the most massive known cluster at z > 1) Simple selection in mass Reichardt et al: arXiv:1203.5775

Followup with Blanco at CTIO or Magellan at Las Campanas 158 confirmed redshifts Median redshift of z = 0.55, max z = 1.37

Cluster Cosmological Constraints Counts vs z can differentiate models for w (and of course σ8

via normalization) Adding cluster constraints to CMB + BAO + H0

+ Sne

Results in a 30-40% improvement in estimate of σ8

and w: σ8 = 0.807 ± 0.027 w = -1.010 ± 0.058

SPTCL constraints currently limited by mass calibration

(Reichardt et al: arXiv:1203.5775)

(B. Benson)

SPT-SZ Cluster Cosmological Constraints 2500 deg2 (projected)

Constrain 𝜹w ~ 5%, independent of geometric cosmological constraints from Supernova, BAO

Systematic test of dark energy paradigm

5’

Foley et al 2011

SZ + Optical"

Phoenix Cluster"z=0.596

Hubble"

20 kpc

Virial mass of 2.5x1015 M, z = 0.6 ""Most X-ray luminous cluster known in the Universe Largest star formation rate observed in a cluster’s brightest central galaxy: (~800 +/- 40 M/ yr) Star formation efficiency of ~30%; “classical” X-ray cooling rate of 2850 M/ yr is efficiently turning into stars

SPT-CL J2344-4243: The “Phoenix Cluster”

McDonald et al. (2012, 2013)

Fine-scale CMB Anisotropy

Primary CMB anisotropy

Story et al. (arXiv:1210.7231)

(Story et al: 1210.7231)

Improved constraints on Inflationary model parameters, the scalar tilt of the primordial power spectrum (ns) and tensor-to-scalar ratio (r)

ns < 1 at 6-sigma: •  • ns = 0.9538 +/- 0.0081

Tensor-to-scalar ratio (CMB only):

r < 0.18 at 95% confidence

Tensor-to-scalar ratio (CMB + BAO + SNe)

r < 0.11 at 95% confidence

(c.f. r < 0.7 at 95% confidence from B-modes, BICEP)

SPT Inflation Constraints

(tensor/scalar) ratio "

New constraints on the effective number of neutrinos and the sum of neutrino masses:

Number of neutrinos:

Neff = 3.86 ± 0.37

(Neff > 3.046 at > 2-sigma) •  Neutrino masses:

Σmν = (0.51 ± 0.15) eV See Hou et al. (arXiv:1212.6267)

SPT Neutrino Constraints

Hou et al. (arXiv:1212.6267)

Benson et al. (arXiv:1112.5435)

Secondary CMB Anisotropy

Below l ~ 3000 All frequencies dominated by primordial CMB Above l ~ 3000: Multi-band data allows spectral separation of diffuse components:

Detect diffuse thermal SZ Detection of power from dusty SFGs

Reichardt et al. 2012 arXiv:1111:0932

Story, et al., 2012 arXiv:1210.7231

Hall et al, arXiv:0912.4315

Gravitational Lensing Detection

Early attempts to include lensing component Demonstrated a strong preference for Alens > 0. SPT has now measured:

Alens = 0.9 ± 0.19

SPT has also measured lensing power spectrum with high SNR from 1/5 of the survey Project a ~20 σ detection from the full data set

Can also reconstruct the lensing potential Compare with galaxy surveys: Blanco, WISE and Spitzer. In all cases we detect significant cross-correlation First detection of galaxy bias

(van Engelen et al: arXiv:1202.0546)

(Bleem et al: arXiv:1203.4808)

Gravitational Lensing

Now have SNR > 1 mass map from 2500 deg2 survey Field should be covered by DES and VISTA surveys

Sub-mm Sources

Discovered ~1500 sources above 4.5 σ in ~800 deg2 survey Two distinct populations of sources: strong synchrotron, and dusty sources with no counterparts in existing catalogs Predicted that these are the rarest tail of high-redshift SMG population

(Vieira et al, arXiv:0912.2338) (Mocanu et al, arXiv:1306.3470)

ALMA + HST Observations

Targeted 26 brightest sources during ALMA cycle 0 All at high redshift, and all show clear evidence for lensing 10 of the 26 are at z > 4, with two at z > 5.6

(360x) 100 GHz detectors, ! (Argonne National Labs)!

(1176x) 150 GHz detectors (NIST)!

Status: First light Jan. 26, 2012 Started a 4-year, 500 deg2 survey Finished 1st year of survey (100 deg2)

SPTpol A new polarization-sensitive camera for SPT

Credit: B. Benson!

Science Goals B-Modes B-mode measurements should push our 1σ detection limit to r = 0.028 (c.f. r < 0.7 from B-modes (Chiang et al, BICEP), and r < 0.18 at 95% CF from temperature anisotropies alone High SNR detection of B-modes from lensing to separate inflationary and gravitational B-modes σ(Σmν) < 0.1 (4x better than KATRIN) E-modes Good enough measurement of E-mode spectrum to constraint YHe

Clusters And 3x better sensitivity than SPT-SZ will push cluster mass limit down by a factor of 1.3, or ~3 x as many clusters per deg2

SPTpol: 1st Season 100 deg2 CMB Polarization Maps

Q Diff U Diff

~7 µK-arcmin in temperature @ 150 GHz ~10 µK-arcmin in polarization @ 150 GHz

(3 x deeper than SPT-SZ 2500 deg2 survey – expect ~7σ detection of lensing B-modes)

Credit: S. Hoover!

SPTpol: 1st Season 100 deg2 CMB Polarization Maps

E Diff Credit: S. Hoover!

SPTpol Direct Detection of Lensing B-modes

Hanson, Hoover et al: arXiv:1307.5830

CMB lensing potential inferred from Herschel 500 µm

B-mode template predicted from E-mode mixing

Cross correlation detected at 7.7σ First detection of B-modes!

SPTpol: 2nd Season 500 deg2 CMB Polarization Maps

Already have beautiful Temperature map from ~6 weeks of data!

Credit: J. Henning!

SPT-3G A quantum leap in sensitivity

Improved wide-field optical design will allow more than twice as many pixels in the focal plane Mapping speed 40x SPT-SZ, and 20x SPTpol 2500 deg2 survey, like SPT-SZ, but order of magnitude deeper

New type of multi-chroic pixel allows simultaneous imaging at 3 separate frequencies Dual-frequency sinuous antenna design already in the field for PolarBear

Unprecedented coverage of 100 deg2 deep field: already covered in IR with Spitzer and Herschel, will be observed by DES in optical, Dedicated XMM-Newton program to cover in Xrays

Science Goals B-Modes B-mode measurements should push our 1σ detection limit to r = 0.01, or r < 0.021 at 95% CF from temperature anisotropies, order of magnitude improvement over current limits High SNR detection of B-modes from lensing to separate inflationary and gravitational B-modes σ(Σmν) < 0.06 (6x better than KATRIN) E-modes Robustly detect kSZ with 1σ sensitivity 0.125 µK2 , or σ(δz) ~ 0.25 on the duration of reionization Measure lensing modes out to l = 800, 150σ detection Cross-correlation with DES can measure galaxy bias to 1% Clusters SPT-3G will survey 2500 deg2 to level 10x deeper than SPT-SZ Order of magnitude more clusters than SPT-SZ, ~4000 above SNR of 5

Cyan: Planck Purple: SPTpol Black: SPT-3G

Purple: Planck Red: SPT-3G

The National Science Foundation

External Advisory Board Meeting – April 16 - 18, 2013!

" SPT-SZ survey complete with many broad science results:

•  High-redshift galaxies: Early star and galaxy formation •  Distant, massive clusters: Dark energy, neutrinos, cluster evolution •  Primordial CMB anisotropy: Inflation, early universe physics •  CMB lensing: “weighing” galaxies, neutrinos •  Data release of 100 deg2 deep field at:

http://pole.uchicago.edu/public/data/maps/ra5h30dec-55 and also from the NASA Legacy Archive for Microwave Background Data Analysis (LAMBDA) server

SPTpol survey is ~1.5 years into 4 year survey:

•  Lensing B-modes: now detected, improve neutrino constraints •  Inflationary B-modes: Improve constraints on inflation’s energy scale •  Clusters: 1.3x deeper in mass, or 3x as many clusters/deg2

SPT-3G:

•  Detector and technological development underway, with broad collaboration between KICP/ANL, UCB, NIST/CU, McGill, CWRU

•  “Weighing” the universe with CMB lensing

!

Thank You!