W. L. Holzapfel

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The past several years have seen the emergence of a standard cosmological model, in which small temperature differences in the cosmic microwave background (CMB) radiation on angular scales of the order of a degree are understood to arise from acoustic oscillations in the hot plasma of the early Universe, arising from primordial density fluctuations. Within(More)
A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required(More)
In this paper, we present results from the complete set of cosmic microwave background (CMB) radiation temperature anisotropy observations made with the Arcminute Cosmology Bolometer Array Receiver (ACBAR) operating at 150 GHz. We include new data from the final 2005 observing season, expanding the number of detector-hours by 210% and the sky coverage by(More)
The Degree Angular Scale Interferometer (DASI) has measured the power spectrum of the Cosmic Microwave Background anisotropy over the range of spherical harmonic multipoles 100 < l < 900. We compare this data, in combination with the COBE-DMR results, to a seven dimensional grid of adiabatic CDM models. Adopting the priors h > 0.45 and 0.0 ≤ τ c ≤ 0.4, we(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 made observations throughout the following austral winter. We present a measurement of the CMB angular(More)
– 2 – Using the Cosmic Background Imager, a 13-element interferometer array operating in the 26–36 GHz frequency band, we have observed 40 deg 2 of sky in three pairs of fields, each ∼ 145 ′ × 165 ′ , using overlapping pointings (mosaicing). We present images and power spectra of the cosmic microwave background radiation in these mosaic fields. We remove(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)
Polarization observations of the cosmic microwave background with the Cosmic Background Imager from September 2002 to May 2004 provide a significant detection of the E-mode polarization and reveal an angular power spectrum of polarized emission showing peaks and valleys that are shifted in phase by half a cycle relative to those of the total intensity(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 2.1 m 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(More)
We report measurements of anisotropy in the cosmic microwave background radiation over the multi-pole range ℓ ∼ 200 → 3500 with the Cosmic Background Imager based on deep observations of three fields. These results confirm the drop in power with increasing ℓ first reported in earlier measurements with this instrument, and extend the observations of this(More)