K. L. Thompson

Improved Constraints on Cosmology and Foregrounds from BICEP2 and Keck Array Cosmic Microwave Background Data with Inclusion of 95 GHz Band

We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.Keck Array and BICEP2 Collaborations: P. A. R. Ade, Z. Ahmed, 3 R. W. Aikin, K. D. Alexander, D. Barkats, S. J. Benton, C. A. Bischoff, J. J. Bock, 7 R. Bowens-Rubin, J. A. Brevik, I. Buder, E. Bullock, V. Buza, 9 J. Connors, B. P. Crill, L. Duband, C. Dvorkin, J. P. Filippini, 11 S. Fliescher, J. Grayson, M. Halpern, S. Harrison, G. C. Hilton, H. Hui, K. D. Irwin, 2, 14 K. S. Karkare, E. Karpel, J. P. Kaufman, B. G. Keating, S. Kefeli, S. A. Kernasovskiy, J. M. Kovac, 9, ∗ C. L. Kuo, 2 E. M. Leitch, M. Lueker, K. G. Megerian, C. B. Netterfield, 17 H. T. Nguyen, R. O’Brient, 7 R. W. Ogburn IV, 2 A. Orlando, 15 C. Pryke, 8, † S. Richter, R. Schwarz, C. D. Sheehy, 16 Z. K. Staniszewski, 7 B. Steinbach, R. V. Sudiwala, G. P. Teply, 15 K. L. Thompson, 2 J. E. Tolan, C. Tucker, A. D. Turner, A. G. Vieregg, 18, 16 A. C. Weber, D. V. Wiebe, J. Willmert, C. L. Wong, 9 W. L. K. Wu, and K. W. Yoon 2 School of Physics and Astronomy, Cardiff University, Cardiff, CF24 3AA, United Kingdom Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, California 94025, USA Department of Physics, Stanford University, Stanford, California 94305, USA Department of Physics, California Institute of Technology, Pasadena, California 91125, USA Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS 42, Cambridge, Massachusetts 02138, USA Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada Jet Propulsion Laboratory, Pasadena, California 91109, USA Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA Department of Physics, Harvard University, Cambridge, MA 02138, USA Service des Basses Températures, Commissariat à l’Energie Atomique, 38054 Grenoble, France Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, V6T 1Z1, Canada National Institute of Standards and Technology, Boulder, Colorado 80305, USA Department of Physics, University of California at San Diego, La Jolla, California 92093, USA Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637, USA Canadian Institute for Advanced Research, Toronto, Ontario, M5G 1Z8, Canada Department of Physics, Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, USA (Published in PRL 20 January 2016)

Improved Measurements of the Temperature and Polarization of the Cosmic Microwave Background from QUaD

We present an improved analysis of the final data set from the QUaD experiment. Using an improved technique to remove ground contamination, we double the effective sky area and hence increase the precision of our cosmic microwave background (CMB) power spectrum measurements by ~30% versus that previously reported. In addition, we have improved our modeling of the instrument beams and have reduced our absolute calibration uncertainty from 5% to 3.5% in temperature. The robustness of our results is confirmed through extensive jackknife tests, and by way of the agreement that we find between our two fully independent analysis pipelines. For the standard six-parameter ΛCDM model, the addition of QUaD data marginally improves the constraints on a number of cosmological parameters over those obtained from the WMAP experiment alone. The impact of QUaD data is significantly greater for a model extended to include either a running in the scalar spectral index, or a possible tensor component, or both. Adding both the QUaD data and the results from the Arcminute Cosmology Bolometer Array Receiver experiment, the uncertainty in the spectral index running is reduced by ~25% compared to WMAP alone, while the upper limit on the tensor-to-scalar ratio is reduced from r < 0.48 to r < 0.33 (95% c.l.). This is the strongest limit on tensors to date from the CMB alone. We also use our polarization measurements to place constraints on parity-violating interactions to the surface of last scattering, constraining the energy scale of Lorentz violating interactions to <1.5 × 10^(–43) GeV (68% c.l.). Finally, we place a robust upper limit on the strength of the lensing B-mode signal. Assuming a single flat band power between l = 200 and l = 2000, we constrain the amplitude of B-modes to be <0.57 μK^2 (95% c.l.).

SPT-3G: a next-generation cosmic microwave background polarization experiment on the South Pole telescope

We describe the design of a new polarization sensitive receiver, spt-3g, for the 10-meter South Pole Telescope (spt). The spt-3g receiver will deliver a factor of ~20 improvement in mapping speed over the current receiver, spt-pol. The sensitivity of the spt-3g receiver will enable the advance from statistical detection of B-mode polarization anisotropy power to high signal-to-noise measurements of the individual modes, i.e., maps. This will lead to precise (~0.06 eV) constraints on the sum of neutrino masses with the potential to directly address the neutrino mass hierarchy. It will allow a separation of the lensing and inflationary B-mode power spectra, improving constraints on the amplitude and shape of the primordial signal, either through spt-3g data alone or in combination with bicep2/keck, which is observing the same area of sky. The measurement of small-scale temperature anisotropy will provide new constraints on the epoch of reionization. Additional science from the spt-3g survey will be significantly enhanced by the synergy with the ongoing optical Dark Energy Survey (des), including: a 1% constraint on the bias of optical tracers of large-scale structure, a measurement of the differential Doppler signal from pairs of galaxy clusters that will test General Relativity on ~200Mpc scales, and improved cosmological constraints from the abundance of clusters of galaxies

Second and Third Season QUaD Cosmic Microwave Background Temperature and Polarization Power Spectra

We report results from the second and third seasons of observation with the QUaD experiment. Angular power spectra of the cosmic microwave background are derived for both temperature and polarization at both 100 GHz and 150 GHz, and as cross-frequency spectra. All spectra are subjected to an extensive set of jackknife tests to probe for possible systematic contamination. For the implemented data cuts and processing technique such contamination is undetectable. We analyze the difference map formed between the 100 and 150 GHz bands and find no evidence of foreground contamination in polarization. The spectra are then combined to form a single set of results which are shown to be consistent with the prevailing LCDM model. The sensitivity of the polarization results is considerably better than that of any previous experiment—for the first time multiple acoustic peaks are detected in the E-mode power spectrum at high significance.

Polarimetry and spectrophotometry of the QSO IRAS 13349 + 2438 and the unification of active galaxies

We have made new observations of the bright (V=14.7) infrared-selected QSO IRAS 13349+2438 (Beichman et al.), which provide important clues about the structure of the inner few parsecs of active galactic nuclei (AGNs). The principal observational facts are as follows: 1. There is high linear optical polarization, increasing with decreasing wavelength from 1.4% at 2.2 μm (K-band) to 8% at 0.36 μm (U-band). 2. The position angle of polarization is independent of wavelength in the optical region and is aligned with the direction of elongation of the r-band optical image, presumably the major axis of the host galaxy

BICEP2 / Keck Array V: Measurements of B-mode polarization at degree angular scales and 150 GHz by the Keck Array

The Keck Array is a system of cosmic microwave background polarimeters, each similar to the Bicep2 experiment. In this paper we report results from the 2012 to 2013 observing seasons, during which the Keck Array consisted of five receivers all operating in the same (150 GHz) frequency band and observing field as Bicep2. We again find an excess of B-mode power over the lensed-ΛCDM expectation of >5σ in the range 30 6σ.

First Season QUaD CMB Temperature and Polarization Power Spectra

QUaD is a bolometric CMB polarimeter sited at the South Pole, operating at frequencies of 100 and 150 GHz. In this paper we report preliminary results from the first season of operation (austral winter 2005). All six CMB power spectra are presented derived as cross spectra between the 100 and 150 GHz maps using 67 days of observation in a low foreground region of approximately 60 deg2. These data are a small fraction of the data acquired to date. The measured spectra are consistent with the ΛCDM cosmological model. We perform jackknife tests that indicate that the observed signal has negligible contamination from instrumental systematics. In addition, by using a frequency jackknife we find no evidence for foreground contamination.

Peculiar Velocity Limits from Measurements of the Spectrum of the Sunyaev-Zeldovich Effect in Six Clusters of Galaxies

We have made measurements of the Sunyaev-Zeldovich (SZ) effect in six galaxy clusters at z > 0.2 using the Sunyaev-Zeldovich Infrared Experiment (SuZIE II) in three frequency bands between 150 and 350 GHz. Simultaneous multifrequency measurements have been used to distinguish between thermal and kinematic components of the SZ effect and to significantly reduce the effects of variations in atmospheric emission that can otherwise dominate the noise. We have set limits to the peculiar velocities of each cluster with respect to the Hubble flow and have used the cluster sample to set a 95% confidence limit of less than 1420 km s-1 to the bulk flow of the intermediate-redshift universe in the direction of the cosmic microwave background dipole. This is the first time that SZ measurements have been used to constrain bulk flows. We show that systematic uncertainties in peculiar velocity determinations from the SZ effect are likely to be dominated by submillimeter point sources, and we discuss the level of this contamination.

Parity Violation Constraints Using Cosmic Microwave Background Polarization Spectra from 2006 and 2007 Observations by the QUaD Polarimeter

(The QUaD Collaboration) Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University, Stanford, CA 94305, USA. School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, UK. California Institute of Technology, Pasadena, CA 91125, USA. Jet Propulsion Laboratory, Pasadena, CA 91109, USA. School of Physics and Astronomy, Cardiff University, Queen’s Buildings, The Parade, Cardiff CF24 3AA, UK. Cavendish Laboratory, University of Cambridge, Cambridge CB3 OHE, UK. Department of Experimental Physics, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland. CENTRA, Departamento de Fisica, Universidade Tecnica de Lisboa, 1049-001 Lisboa, Portugal. Institute for Astronomy, University of Edinburgh, Edinburgh EH9 3HJ, UK. Kavli Institute for Cosmological Physics, Department of Astronomy & Astrophysics, Enrico Fermi Institute, University of Chicago,Chicago, IL 60637, USA. Laboratoire APC/CNRS, Bâtiment Condorcet, 75205 Paris Cedex 13, France. School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.

BICEP3: A 95GHz refracting telescope for degree-scale CMB polarization

Bicep3 is a 550 mm-aperture refracting telescope for polarimetry of radiation in the cosmic microwave background at 95 GHz. It adopts the methodology of Bicep1, Bicep2 and the Keck Array experiments | it possesses sufficient resolution to search for signatures of the inflation-induced cosmic gravitational-wave background while utilizing a compact design for ease of construction and to facilitate the characterization and mitigation of systematics. However, Bicep3 represents a significant breakthrough in per-receiver sensitivity, with a focal plane area 5x larger than a Bicep2/Keck Array receiver and faster optics (f=1:6 vs. f=2:4). Large-aperture infrared-reflective metal-mesh filters and infrared-absorptive cold alumina filters and lenses were developed and implemented for its optics. The camera consists of 1280 dual-polarization pixels; each is a pair of orthogonal antenna arrays coupled to transition-edge sensor bolometers and read out by multiplexed SQUIDs. Upon deployment at the South Pole during the 2014-15 season, Bicep3 will have survey speed comparable to Keck Array 150 GHz (2013), and will signifcantly enhance spectral separation of primordial B-mode power from that of possible galactic dust contamination in the Bicep2 observation patch