W. L. Holzapfel

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J. M. Kovac*†‡, E. M. Leitch§†‡, C. Pryke§†‡k, J. E. Carlstrom§*†‡k, N. W. Halverson{† & W. L. Holzapfel{† * Department of Physics; † Center for Astrophysical Research in Antarctica; ‡ Center for Cosmological Physics; § Department of Astronomy & Astrophysics and k Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois(More)
Measurements of the cosmic microwave background (CMB) radiation can reveal with remarkable precision the conditions of the Universe when it was approximately 400,000 years old. The three most fundamental properties of the CMB are its frequency spectrum (which determines the temperature), and the fluctuations in both the temperature and polarization across a(More)
We present a formalism for analyzing interferometric observations of the Cosmic Microwave Background (CMB) anisotropy and polarization. The formalism is based upon the l-space expansion of the angular power spectrum favored in recent years. Explicit discussions of maximum likelihood analysis, power spectrum reconstruction, parameter estimation, imaging and(More)
We describe the Arcminute Cosmology Bolometer Array Receiver (Acbar); a multifrequency millimeter-wave receiver designed for observations of the Cosmic Microwave Background (CMB) and the Sunyaev-Zel’dovich effect in clusters of galaxies. The Acbar focal plane consists of a 16-pixel, background-limited, 240 mK bolometer array that can be configured to(More)
Background Imaging of Cosmic Extragalactic Polarization (Bicep) is a bolometric polarimeter designed to measure the inflationary B-mode polarization of the cosmic microwave background (CMB) at degree angular scales. During three seasons of observing at the South Pole (2006 through 2008), Bicep mapped ∼2% of the sky chosen to be uniquely clean of polarized(More)
We report improved measurements of temperature anisotropies in the cosmic microwave background (CMB) radiation made with the Arcminute Cosmology Bolometer Array Receiver (ACBAR). In this paper, we use a new analysis technique and include 30% more data from the 2001 and 2002 observing seasons than the first release (Kuo et al. 2004) to derive a new set of(More)
We report the first measurements of anisotropy in the cosmic microwave background (CMB) radiation with the Arcminute Cosmology Bolometer Array Receiver (Acbar). The instrument was installed on the 2.1m Viper telescope at the South Pole in January 2001; the data presented here are the product of observations up to and including July 2002. The two deep fields(More)
We report the design and performance of 300-mK composite bolometers that use micromesh absorbers and support structures patterned from thin films of low-stress silicon nitride. The small geometrical filling factor of the micromesh absorber provides 20x reduction in heat capacity and cosmic ray cross section relative to a solid absorber with no loss in(More)
We present measurements of anisotropy in the cosmic microwave background (CMB) from the first season of observations with the Degree Angular Scale Interferometer (DASI). The instrument was deployed at the South Pole in the austral summer 1999–2000, and we made observations throughout the following austral winter. We present a measurement of the CMB angular(More)
Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this Letter we present the first detection of(More)