J. Hubmayr

SPTpol: an instrument for CMB polarization measurements with the South Pole Telescope

SPTpol is a dual-frequency polarization-sensitive camera that was deployed on the 10-meter South Pole Telescope in January 2012. SPTpol will measure the polarization anisotropy of the cosmic microwave background (CMB) on angular scales spanning an arcminute to several degrees. The polarization sensitivity of SPTpol will enable a detection of the CMB “B-mode” polarization from the detection of the gravitational lensing of the CMB by large scale structure, and a detection or improved upper limit on a primordial signal due to inationary gravity waves. The two measurements can be used to constrain the sum of the neutrino masses and the energy scale of ination. These science goals can be achieved through the polarization sensitivity of the SPTpol camera and careful control of systematics. The SPTpol camera consists of 768 pixels, each containing two transition-edge sensor (TES) bolometers coupled to orthogonal polarizations, and a total of 1536 bolometers. The pixels are sensitive to light in one of two frequency bands centered at 90 and 150 GHz, with 180 pixels at 90 GHz and 588 pixels at 150 GHz. The SPTpol design has several features designed to control polarization systematics, including: singlemoded feedhorns with low cross-polarization, bolometer pairs well-matched to dfference atmospheric signals, an improved ground shield design based on far-sidelobe measurements of the SPT, and a small beam to reduce temperature to polarization leakage. We present an overview of the SPTpol instrument design, project status, and science projections.

A MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND GRAVITATIONAL LENSING POTENTIAL FROM 100 SQUARE DEGREES OF SPTPOL DATA

We present a measurement of the cosmic microwave background (CMB) gravitational lensing potential using data from the first two seasons of observations with SPTpol, the polarization-sensitive receiver currently installed on the South Pole Telescope. The observations used in this work cover 100 deg^2 of sky with arcminute resolution at 150 GHz. Using a quadratic estimator, we make maps of the CMB lensing potential from combinations of CMB temperature and polarization maps. We combine these lensing potential maps to form a minimum-variance (MV) map. The lensing potential is measured with a signal-to-noise ratio of greater than one for angular multipoles between 100 < L < 250. This is the highest signal-to-noise mass map made from the CMB to date and will be powerful in cross-correlation with other tracers of large-scale structure. We calculate the power spectrum of the lensing potential for each estimator, and we report the value of the MV power spectrum between 100 < L < 2000 as our primary result. We constrain the ratio of the spectrum to a fiducial ΛCDM model to be A_(MV) = 0.92 ± 0.14 (Stat.) ± 0.08 (Sys.). Restricting ourselves to polarized data only, we find A_(POL) = 0.92 ± 0.24 (Stat.) ± 0.11 (Sys.). This measurement rejects the hypothesis of no lensing at 5.9σ using polarization data alone, and at 14σ using both temperature and polarization data.

The Atacama Cosmology Telescope: Two-Season ACTPol Spectra and Parameters

Author(s): Louis, T; Grace, E; Hasselfield, M; Lungu, M; Maurin, L; Addison, GE; Ade, PAR; Aiola, S; Allison, R; Amiri, M; Angile, E; Battaglia, N; Beall, JA; De Bernardis, F; Bond, JR; Britton, J; Calabrese, E; Cho, HM; Choi, SK; Coughlin, K; Crichton, D; Crowley, K; Datta, R; Devlin, MJ; Dicker, SR; Dunkley, J; Dunner, R; Ferraro, S; Fox, AE; Gallardo, P; Gralla, M; Halpern, M; Henderson, S; Hill, JC; Hilton, GC; Hilton, M; Hincks, AD; Hlozek, R; Patty Ho, SP; Huang, Z; Hubmayr, J; Huffenberger, KM; Hughes, JP; Infante, L; Irwin, K; Kasanda, SM; Klein, J; Koopman, B; Kosowsky, A; Li, D; Madhavacheril, M; Marriage, TA; McMahon, J; Menanteau, F; Moodley, K; Munson, C; Naess, S; Nati, F; Newburgh, L; Nibarger, J; Niemack, MD; Nolta, MR; Nunez, C; Page, LA; Pappas, C; Partridge, B; Rojas, F; Schaan, E; Schmitt, BL; Sehgal, N; Sherwin, BD; Sievers, J; Simon, S; Spergel, DN; Staggs, ST; Switzer, ER; Thornton, R; Trac, H; Treu, J; Tucker, C; Engelen, AV; Ward, JT; Wollack, EJ | Abstract:

Photon-noise limited sensitivity in titanium nitride kinetic inductance detectors

We demonstrate photon-noise limited performance at sub-millimeter wavelengths in feedhorn-coupled, microwave kinetic inductance detectors made of a TiN/Ti/TiN trilayer superconducting film, tuned to have a transition temperature of 1.4 K. Micro-machining of the silicon-on-insulator wafer backside creates a quarter-wavelength backshort optimized for efficient coupling at 250 μm. Using frequency read out and when viewing a variable temperature blackbody source, we measure device noise consistent with photon noise when the incident optical power is >0.5 pW, corresponding to noise equivalent powers >3×10−17 W/Hz. This sensitivity makes these devices suitable for broadband photometric applications at these wavelengths.

Measurements of E-mode polarization and temperature-E-mode correlation in the cosmic microwave background from 100 square degrees of SPTPOL data

We present measurements of E-mode polarization and temperature-E-mode correlation in the cosmic microwave background using data from the first season of observations with SPTpol, the polarization-sensitive receiver currently installed on the South Pole Telescope (SPT). The observations used in this work cover 100 deg^2 of sky with arcminute resolution at 150 GHz. We report the E-mode angular auto-power spectrum (EE) and the temperature-E-mode angular cross-power spectrum (TE) over the multipole range 500 < l ≤ 5000. These power spectra improve on previous measurements in the high-l (small-scale) regime. We fit the combination of the SPTpol power spectra, data from Planck, and previous SPT measurements with a six-parameter ΛCDM cosmological model. We find that the best-fit parameters are consistent with previous results. The improvement in high-l sensitivity over previous measurements leads to a significant improvement in the limit on polarized point-source power: after masking sources brighter than 50 mJy in unpolarized flux at 150 GHz, we find a 95% confidence upper limit on unclustered point-source power in the EE spectrum of D_l = l(l + 1) C_l/2π < 0.40 µK^2 at l = 3000, indicating that future EE measurements will not be limited by power from unclustered point sources in the multipole range l < 3600, and possibly much higher in l.

Evidence for the kinematic Sunyaev-Zel'dovich effect with the Atacama Cosmology Telescope and velocity reconstruction from the Baryon Oscillation Spectroscopic Survey

Emmanuel Schaan, ∗ Simone Ferraro, 2 Mariana Vargas-Magaña, Kendrick M. Smith, Shirley Ho, Simone Aiola, Nicholas Battaglia, J. Richard Bond, Francesco De Bernardis, Erminia Calabrese, 9 Hsiao-Mei Cho, Mark J. Devlin, Joanna Dunkley, Patricio A. Gallardo, Matthew Hasselfield, Shawn Henderson, J. Colin Hill, Adam D. Hincks, Renée Hlozek, Johannes Hubmayr, John P. Hughes, Kent D. Irwin, 10 Brian Koopman, Arthur Kosowsky, Dale Li, Thibaut Louis, Marius Lungu, Mathew Madhavacheril, Löıc Maurin, Jeffrey John McMahon, Kavilan Moodley, Sigurd Naess, Federico Nati, Laura Newburgh, Michael D. Niemack, Lyman A. Page, Christine G. Pappas, Bruce Partridge, Benjamin L. Schmitt, Neelima Sehgal, Blake D. Sherwin, 2 Jonathan L. Sievers, 26 David N. Spergel, Suzanne T. Staggs, Alexander van Engelen, and Edward J. Wollack Dept. of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ USA 08544 Miller Institute for Basic Research in Science, University of California, Berkeley, CA, 94720, USA Instituto de Fisica, Universidad Nacional Autónoma de México, Apdo. Postal 20-364, México Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5, Canada Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 USA and Pittsburgh Particle Physics, Astrophysics, and Cosmology Center, University of Pittsburgh, Pittsburgh PA 15260 Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON, Canada M5S 3H8 Department of Physics, Cornell University, Ithaca, NY 14853, USA Sub-Department of Astrophysics, University of Oxford, Keble Road, Oxford, UK OX1 3RH SLAC National Accelerator Laboratory, 2575 Sandhill Hill Road, Menlo Park, CA 94025 Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA, USA 19104 Dept. of Astronomy, Pupin Hall, Columbia University, New York, NY, USA 10027 UBC (University of British Columbia, Department of Physics and Astronomy, 6224 Agricultural Road, Vancouver BC V6T 1Z1, Canada) National Institute of Standards and Technology, Boulder, CO USA 80305 Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, NJ 08854-8019 Dept. of Physics, Stanford, CA 94305 Physics and Astronomy Department, Stony Brook University, Stony Brook, NY USA 11794 Instituto de Astrof́ısica, Pontifićıa Universidad Católica de Chile, Santiago, Chile Department of Physics, University of Michigan, Ann Arbor, USA 48103 Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Durban 4041, South Africa Dunlap Institute, University of Toronto, 50 St. George St., Toronto ON M5S3H4 Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ, USA 08544 Department of Physics and Astronomy, Haverford College, Haverford, PA, USA 19041 Berkeley Center for Cosmological Physics, LBL and Department of Physics, University of California, Berkeley, CA, USA 94720 Astrophysics and Cosmology Research Unit, School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4041, South Africa National Institute for Theoretical Physics (NITheP), University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa NASA/Goddard Space Flight Center, Greenbelt, MD, USA 20771

Two-season Atacama Cosmology Telescope polarimeter lensing power spectrum

Blake D. Sherwin, Alexander van Engelen, Neelima Sehgal, Mathew Madhavacheril, 3 Graeme E. Addison, Simone Aiola, 7, 8 Rupert Allison, Nicholas Battaglia, Daniel T. Becker, James A. Beall, J. Richard Bond, Erminia Calabrese, Rahul Datta, Mark J. Devlin, Rolando Dünner, Joanna Dunkley, 4, 11 Anna E. Fox, Patricio Gallardo, Mark Halpern, Matthew Hasselfield, 18 Shawn Henderson, J. Colin Hill, Gene C. Hilton, Johannes Hubmayr, John P. Hughes, Adam D. Hincks, Renée Hlozek, Kevin M. Huffenberger, Brian Koopman, Arthur Kosowsky, 8 Thibaut Louis, Löıc Maurin, Jeff McMahon, Kavilan Moodley, Sigurd Naess, 11 Federico Nati, Laura Newburgh, Michael D. Niemack, Lyman A. Page, Jonathan Sievers, David N. Spergel, 26 Suzanne T. Staggs, Robert J. Thornton, 13 Jeff Van Lanen, Eve Vavagiakis, and Edward J. Wollack Berkeley Center for Cosmological Physics, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720 Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON, Canada M5S 3H8 Physics and Astronomy Department, Stony Brook University, Stony Brook, NY 11794 Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 Dept. of Physics and Astronomy, The Johns Hopkins University,

Corrugated silicon platelet feed horn array for CMB polarimetry at 150 GHz

Next generation cosmic microwave background (CMB) polarization anisotropy measurements will feature focal plane arrays with more than 600 millimeter-wave detectors. We make use of high-resolution photolithography and wafer-scale etch tools to build planar arrays of corrugated platelet feeds in silicon with highly symmetric beams, low cross-polarization and low side lobes. A compact Au-plated corrugated Si feed designed for 150 GHz operation exhibited performance equivalent to that of electroformed feeds: ~ -0.2 dB insertion loss, < -20 dB return loss from 120 GHz to 170 GHz, < -25 dB side lobes and < -23 dB cross-polarization. We are currently fabricating a 50mm diameter array with 84 horns consisting of 33 Si platelets as a prototype for the SPTpol and ACTpol telescopes. Our fabrication facilities permit arrays up to 150mm in diameter.

Fabrication of large dual-polarized multichroic TES bolometer arrays for CMB measurements with the SPT-3G camera

This work presents the procedures used at Argonne National Laboratory to fabricate large arrays of multichroic transition-edge sensor (TES) bolometers for cosmic microwave background (CMB) measurements. These detectors will be assembled into the focal plane for the SPT-3G camera, the third generation CMB camera to be installed in the South Pole Telescope. The complete SPT-3G camera will have approximately 2690 pixels, for a total of 16 140 TES bolometric detectors. Each pixel is comprised of a broad-band sinuous antenna coupled to a Nb microstrip line. In-line filters are used to define the different bands before the millimeter-wavelength signal is fed to the respective Ti/Au TES bolometers. There are six TES bolometer detectors per pixel, which allow for measurements of three band-passes (95, 150 and 220 GHz) and two polarizations. The steps involved in the monolithic fabrication of these detector arrays are presented here in detail. Patterns are defined using a combination of stepper and contact lithography. The misalignment between layers is kept below 200 nm. The overall fabrication involves a total of 16 processes, including reactive and magnetron sputtering, reactive ion etching, inductively coupled plasma etching and chemical etching.

Measurements of the Temperature and E-mode Polarization of the CMB from 500 Square Degrees of SPTpol Data

We present measurements of the