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arXiv · 1311.1879

B-Machine Polarimeter: A Telescope to Measure the Polarization of the Cosmic Microwave Background

Brian D. Williams
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Abstract

The B-Machine Telescope is the culmination of several years of development, construction, characterization and observation. The telescope is a departure from standard polarization chopping of correlation receivers to a half wave plate technique. Typical polarimeters use a correlation receiver to chop the polarization signal to overcome the $1/f$ noise inherent in HEMT amplifiers. B-Machine uses a room temperature half wave plate technology to chop between polarization states and measure the polarization signature of the CMB. The telescope has a demodulated $1/f$ knee of 5 mHz and an average sensitivity of 1.6 $\mathrm{mK}\sqrt{\mathrm{s}}$. This document examines the construction, characterization, observation of astronomical sources, and data set analysis of B-Machine. Preliminary power spectra and sky maps with large sky coverage for the first year data set are included.

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Brian D. Williams. 2013-11-08. B-Machine Polarimeter: A Telescope to Measure the Polarization of the Cosmic Microwave Background. https://arxiv.org/abs/1311.1879

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