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arXiv · 1407.5928

BICEP3: a 95 GHz refracting telescope for degree-scale CMB polarization

Z. Ahmed·M. Amiri·S. J. Benton·J. J. Bock·R. Bowens-Rubin·I. Buder·E. Bullock·J. Connors·J. P. Filippini·J. A. Grayson·M. Halpern·G. C. Hilton·V. V. Hristov·H. Hui·K. D. Irwin·J. Kang·K. S. Karkare·E. Karpel·J. M. Kovac·C. L. Kuo·C. B. Netterfield·H. T. Nguyen·R. O'Brient·R. W. Ogburn IV·C. Pryke·C. D. Reintsema·S. Richter·K. L. Thompson·A. D. Turner·A. G. Vieregg·W. L. K. Wu·K. W. Yoon
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Abstract

BICEP3 is a 550 mm-aperture refracting telescope for polarimetry of radiation in the cosmic microwave background at 95 GHz. It adopts the methodology of BICEP1, BICEP2 and the Keck Array experiments - it possesses sufficient resolution to search for signatures of the inflation-induced cosmic gravitational-wave background while utilizing a compact design for ease of construction and to facilitate the characterization and mitigation of systematics. However, BICEP3 represents a significant breakthrough in per-receiver sensitivity, with a focal plane area 5$\times$ larger than a BICEP2/Keck Array receiver and faster optics ($f/1.6$ vs. $f/2.4$). Large-aperture infrared-reflective metal-mesh filters and infrared-absorptive cold alumina filters and lenses were developed and implemented for its optics. The camera consists of 1280 dual-polarization pixels; each is a pair of orthogonal antenna arrays coupled to transition-edge sensor bolometers and read out by multiplexed SQUIDs. Upon deployment at the South Pole during the 2014-15 season, BICEP3 will have survey speed comparable to Keck Array 150 GHz (2013), and will significantly enhance spectral separation of primordial B-mode power from that of possible galactic dust contamination in the BICEP2 observation patch.

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Z. Ahmed, M. Amiri, S. J. Benton, J. J. Bock, R. Bowens-Rubin, I. Buder, E. Bullock, J. Connors, J. P. Filippini, J. A. Grayson, M. Halpern, G. C. Hilton, V. V. Hristov, H. Hui, K. D. Irwin, J. Kang, K. S. Karkare, E. Karpel, J. M. Kovac, C. L. Kuo, C. B. Netterfield, H. T. Nguyen, R. O'Brient, R. W. Ogburn IV, C. Pryke, C. D. Reintsema, S. Richter, K. L. Thompson, A. D. Turner, A. G. Vieregg, W. L. K. Wu, K. W. Yoon. 2014-07-22. BICEP3: a 95 GHz refracting telescope for degree-scale CMB polarization. https://doi.org/10.1117/12.2057224

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