A Spin Modulated Telescope to Make Two Dimensional CMB Maps

J. Staren; P. Meinhold; J. Childers; M. Lim; A. Levy; P. Lubin; M. Seiffert; T. Gaier; N. Figueiredo; T. Villela; C. A. Wuensche; M. Tegmark; A. de Oliveira-Costa

doi:10.1086/309236

arXiv · astro-ph/9912212

A Spin Modulated Telescope to Make Two Dimensional CMB Maps

J. Staren·P. Meinhold·J. Childers·M. Lim·A. Levy·P. Lubin·M. Seiffert·T. Gaier·N. Figueiredo·T. Villela·C. A. Wuensche·M. Tegmark·A. de Oliveira-Costa

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Abstract

We describe the HEMT Advanced Cosmic Microwave Explorer (HACME), a balloon borne experiment designed to measure sub-degree scale Cosmic Microwave Background anisotropy over hundreds of square degrees, using a unique two dimensional scanning strategy. A spinning flat mirror that is canted relative to its spin axis modulates the direction of beam response in a nearly elliptical path on the sky. The experiment was successfully flown in February of 1996, achieving near laboratory performance for several hours at float altitude. A map free of instrumental systematic effects is produced for a 3.5 hour observation of 630 square degrees, resulting in a flat band power upper limit of (l(l+1)C_l/2 pi)^0.5 < 77 microK at l = 38 (95% confidence). The experiment design, flight operations and data, including atmospheric effects and noise performance, are discussed.

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J. Staren, P. Meinhold, J. Childers, M. Lim, A. Levy, P. Lubin, M. Seiffert, T. Gaier, N. Figueiredo, T. Villela, C. A. Wuensche, M. Tegmark, A. de Oliveira-Costa. 1999-12-09. A Spin Modulated Telescope to Make Two Dimensional CMB Maps. https://doi.org/10.1086/309236

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