SPIDER: A balloon-borne CMB polarimeter for large angular scales

Proceedings of SPIE - The International Society for Optical Engineering (Impact Factor: 0.2). 06/2011; 7741. DOI: 10.1117/12.857720
Source: arXiv


We describe SPIDER, a balloon-borne instrument to map the polarization of the
millimeter-wave sky with degree angular resolution. Spider consists of six
monochromatic refracting telescopes, each illuminating a focal plane of
large-format antenna-coupled bolometer arrays. A total of 2,624 superconducting
transition-edge sensors are distributed among three observing bands centered at
90, 150, and 280 GHz. A cold half-wave plate at the aperture of each telescope
modulates the polarization of incoming light to control systematics. Spider's
first flight will be a 20-30-day Antarctic balloon campaign in December 2011.
This flight will map \sim8% of the sky to achieve unprecedented sensitivity to
the polarization signature of the gravitational wave background predicted by
inflationary cosmology. The Spider mission will also serve as a proving ground
for these detector technologies in preparation for a future satellite mission.

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    • "It is expected to map the CMB polarization at angular scales larger than a few degrees, observing over 65% of the sky at 38, 93, 148 and 217 GHz. SPIDER [68] [69] is a balloon-borne instrument designed to probe the possible primordial gravitational wave signal by detecting CMB B-modes at degree angular scales. It involves 2400 pairs of polarization-sensitive bolometers in the 94 GHz and 150 GHz frequency bands and map 7.5% of the sky with a depth of 11 to 14 µK . "
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