Initial Performance of BICEP3: A Degree Angular Scale 95 GHz Band Polarimeter

• Main Authors: Wu, W. L. K., Ade, P. A. R., Ahmed, Z., Alexander, K. D., Amiri, M., Barkats, D., Benton, S. J., Bischoff, C. A., Bock, J. J., Bowens-Rubin, R., Buder, I., Bullock, E., Buza, V., Connors, J. A., Filippini, J. P., Fliescher, S., Grayson, J. A., Halpern, M., Harrison, S. A., Hilton, G. C., Hristov, V. V., Hui, H., Irwin, K. D., Kang, J., Karkare, K. S., Karpel, E., Kefeli, S., Kernasovskiy, S. A., Kovac, J. M., Kuo, C. L., Megerian, K. G., Netterfield, C. B., Nguyen, H. T., O'Brient, R., Ogburn, R. W., Pryke, C., Reintsema, C. D., Richter, S., Sorensen, C., Staniszewski, Z. K., Steinbach, B., Sudiwala, R. V., Teply, G. P., Thompson, K. L., Tolan, J. E., Tucker, C. E., Turner, A. D., Vieregg, A. G., Weber, A. C., Wiebe, D. V., Willmert, J., Yoon, K. W.
• Format: Text
• Language: unknown
• Published: arXiv 2016
• Subjects: Instrumentation and Methods for Astrophysics astro-ph.IM; Cosmology and Nongalactic Astrophysics astro-ph.CO; FOS Physical sciences; Austral; South Pole; South pole
• Online Access: https://dx.doi.org/10.48550/arxiv.1601.00125; https://arxiv.org/abs/1601.00125

BICEP3 is a $550~mm$ aperture telescope with cold, on-axis, refractive optics designed to observe at the $95~GHz$ band from the South Pole. It is the newest member of the BICEP/Keck family of inflationary probes specifically designed to measure the polarization of the cosmic microwave background (CMB) at degree-angular scales. BICEP3 is designed to house 1280 dual-polarization pixels, which, when fully-populated, totals to $\sim$9$\times$ the number of pixels in a single Keck $95~GHz$ receiver, thus further advancing the BICEP/Keck program's $95~GHz$ mapping speed. BICEP3 was deployed during the austral summer of 2014-2015 with 9 detector tiles, to be increased to its full capacity of 20 in the second season. After instrument characterization measurements were taken, CMB observation commenced in April 2015. Together with multi-frequency observation data from Planck, BICEP2, and the Keck Array, BICEP3 is projected to set upper limits on the tensor-to-scalar ratio to $r$ $\lesssim 0.03$ at $95\%$ C.L.. : 7 pages, LTD-16 proceedings