SPIDER: a balloon-borne CMB polarimeter for large angular scales
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 ~8% 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.
Additional Information© 2010 SPIE--The International Society for Optical Engineering. The Spider collaboration gratefully acknowledges the support of NASA (grant number NNX07AL64G), the Gordon and Betty Moore Foundation, and NSERC. WCJ acknowledges the support of the Alfred P. Sloan Foundation. JPF is partially supported by a Moore Postdoctoral Fellowship in Experimental Physics. The Spider collaboration also extends special gratitude to Andrew E. Lange, who passed away on January 22. Andrew was a leading light of the cosmology community and a driving force behind the Spider project. He is greatly missed by his many collaborators, past and present.