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arXiv · 0901.0546

The ARCADE 2 Instrument

J. Singal·D. J. Fixsen·A. Kogut·S. Levin·M. Limon·P. Lubin·P. Mirel·M. Seiffert·T. Villela·E. Wollack·C. A. Wuensche
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Abstract

The second generation Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE 2) instrument is a balloon-borne experiment to measure the radiometric temperature of the cosmic microwave background and Galactic and extra-Galactic emission at six frequencies from 3 to 90 GHz. ARCADE 2 utilizes a double-nulled design where emission from the sky is compared to that from an external cryogenic full-aperture blackbody calibrator by cryogenic switching radiometers containing internal blackbody reference loads. In order to further minimize sources of systematic error, ARCADE 2 features a cold fully open aperture with all radiometrically active components maintained at near 2.7 K without windows or other warm objects, achieved through a novel thermal design. We discuss the design and performance of the ARCADE 2 instrument in its 2005 and 2006 flights.

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J. Singal, D. J. Fixsen, A. Kogut, S. Levin, M. Limon, P. Lubin, P. Mirel, M. Seiffert, T. Villela, E. Wollack, C. A. Wuensche. 2010-04-03. The ARCADE 2 Instrument. https://doi.org/10.1088/0004-637x%2F730%2F2%2F138

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