ACT: the Atacama Cosmology Telescope Mark Devlin – University of Pennsylvania for the ACT Collaboration

ACT: The Atacama Cosmology Telescope Mark Devlin – University of Pennsylvania For the ACT Collaboration

Probing Fundamental Physics Through1 Measurements of Cosmic Structure • 5200 m ACT Site • Latitude -23o • 0.5 mm PWV ->  = 0.02 ALMA 150GHz

(CLASS) ACT PolarBear ACT Site Telescope

Supplies ABS Radio Link to San Pedro

High bay and Control and Equipment Room Workshop

Generators

15,000 liter Diesel Tank 3 ACT Optics

1.3 arcmin at 150 GHz

400 kg 4 ACTPol 1.8 m

OMT TES • 3 Optics Tubes • 1 deg FOV • 80 mK DR Silicon arrays • 100 µW

Feedhorn array

30cm A typical SZE observation with ACT • ACT has 1.3’ resolution at 148 GHz. • ACT images are typically smoothed to 2.4’ for display purposes (see Hincks et al. 2010).

Hincks et al. 2010

ACT taken by the light of a full Moon (30 second exposure)

6 ACT Results 2013 • Cosmological parameters from three seasons of data Sievers et al. El Gordo • Sunyaev-Zel'dovich Selected Galaxy Clusters at 148 GHz Hasselfield et al. • The stellar content of galaxy clusters selected using the Sunyaev-Zel'dovich effect Hilton et al. • Likelihood for small-scale CMB data - Dunkley et al.

2012 • Evidence of Galaxy Cluster Motions with the Kinematic Sunyaev-Zel'dovich Effect Hand et al. - PHYSICS WORLD “Top Ten” Breakthrough for 2012 • The Atacama Cosmology Telescope: ACT-CL J0102-4915 "El Gordo," a Massive Merging Cluster at Redshift 0.87 Menanteau et al. – DISCOVER Magazine #64 Science News 2012 2011 • Detection of the Power Spectrum of Cosmic Microwave Background Lensing Das et al. - PHYSICS TODAY Top Search and Discovery result of 2011 ACTPol First Season Observations (Naess et al, JCAP(2014))

• 11 Sept 2013 – 24 Dec 2013 (500 hrs) • One 150 GHz array installed • Four ~ 70 deg2 patches • Overlap with other surveys for cross-correlation ACTPol First Season Observations (Naess et al, JCAP(2014))

• One of the 4 ACTPol fields: D6 • (Area ~ 60 deg2) Circa –Just before this meeting (November 2014)

• BICEP2 • ACTPol hi-res data • Planck data read off plots • POLARBEAR & ACTPol are direct BB • SPT & “preliminary” ACTPol are indirect lensing BB

Compilation by L. Page

10 We detect halo lensing from 12,000 stacked CMASS galaxies at S/N of 3.2 sigma 13 Best-fit of M200 = 2.0+-1.0 10 Msolar and C200 = 5.4+-0.8 ● Excess seen in all three observing regions

● Signal consistent with Optical Weak Lensing measurement from Miyatake et. al. 2013 Thermal SZ One-Point PDF at 148 GHz Hill et al. (2014) arXiv:1411.8004 — see poster session!

• Simple observable: histogram of pixel temperature values • Use info from all clusters in the map, including SNR<5

• Optimal one-halo term tSZ statistic: very sensitive to σ8 • Build on earlier ACT tSZ skewness measurement (Wilson++ 2012)

Binned Histogram tSZ decrements (negative Tfilt only)

148 GHz Tfilt Thermal SZ One-Point PDF at 148 GHz Hill et al. (2014) arXiv:1411.8004 — see poster session!

~2x smaller than stat. error from tSZ skewness alone (Wilson++12)

likelihood

σ8 Advanced ACTPol (AdvACT)

• Cosmic variance‐limited EE measurement out to ell=2000

• 5x better resolution than Planck with 5x the Planck sensitivity

• 3x more polarization modes than Planck

• New constraints on the CDM cosmology Errors assume 3 seasons of AdvACTPol observations AdvACT Survey Plans

Complete overlap with DES, LSST & DESI survey regions 16 Planck Foreground Level in Effective r

BOSS D56 Chile

BICEP2

r=0.01 r=1 South Pole

17 AdvACT Specifications 20,000 deg2

Detector Array Center Width # TES NETCMB Map Noise Beam [GHz] [GHz] [ࣆࡷ ࢙] ሾࣆࡷ arcmin] arcmin Low Frequency (LF) 28 6 80 35 78 7.1 Low Frequency (LF) 41 19 80 32 71 4.8 Medium Frequency (MF) 90 38.5 1760 5.8 7.8 2.2 MF/HF 150 41 2816 5.4 6.9 1.3 High Frequency (HF) 230 100 1056 20 25 0.9

Half the sky ‐> r=0.01 at 3‐4 ‐> Subdivide to check isotropy

18 Advanced ACTPol (AdvACT)

• New dichroic polarimeters Horn array • Datta et al., JLTP (2014) detector passbands

Assembled Array Detector wafer

• Array to be deployed on ACT in Jan 2015 19 Rotating HWP Provides Stability

• 2Hz rotation ‐> • 8 Hz Modulation ‐> • 800 sec Stability!

Three 30 cm HWPs installed directly in front of the AdvACT receiver AdvACT Will Test Large‐Field Inflation

Can detect r = 0.01 signal

• Can clean synch and dust • Cleaned maps at both 90 and 150 • Can confirm signal is isotropic and that result is independent of foregrounds • Measure B mode spectrum Advanced ACTPol (AdvACT)

Projected to improve LSST’s DE FOM by 20x!

Projected to improve Planck limit on m

22 Big Telescope for Big B‐Modes

23 Antarctica December 2010 BLAST‐Pol 500 μm Inferred B‐Field Direction in Vela C

Background image: 500 μm polarized intensity Contours: 500 μm Total Intensity

4400 Nyquist sampled vectors when smoothed to 2.5 arcmin resolution Coming Soon – BLAST-TNG

• 2.5 meter Carbon Fiber Mirror • 2200 detectors at 250, 350 and 500 m • 22 arcsec resolution at 250 m • 16 times the speed of BLAST-Pol

• First flight December 2016 with Shared Risk Observing THE END 28