A New Limit on CMB Circular Polarization from SPIDER

• Main Authors: Nagy, J. M., Ade, P. A. R., Amiri, M., Benton, S. J., Bergman, A. S., Bihary, R., Bock, J. J., Bond, J. R., Bryan, S. A., Chiang, H. C., Contaldi, C. R., Dore, O., Duivenvoorden, A. J., Eriksen, H. K., Farhang, M., Filippini, J. P., Fissel, L. M., Fraisse, A. A., Freese, K., Galloway, M., Gambrel, A. E., Gandilo, N. N., Ganga, K., Gudmundsson, J. E., Halpern, M., Hartley, J., Hasselfield, M., Hilton, G., Holmes, W., Hristov, V. V., Huang, Z., Irwin, K. D., Jones, W. C., Kuo, C. L., Kermish, Z. D., Li, S., Mason, P. V., Megerian, K., Moncelsi, L., Morford, T. A., Netterfield, C. B., Nolta, M., Padilla, I. L., Racine, B., Rahlin, A. S., Reintsema, C., Ruhl, J. E., Runyan, M. C., Ruud, T. M., Shariff, J. A., Soler, J. D., Song, X., Trangsrud, A., Tucker, C., Tucker, R. S., Turner, A. D., van der List, J. F., Weber, A. C., Wehus, I. K., Wiebe, D. V., Young, E. Y.
• Format: Text
• Language: unknown
• Published: arXiv 2017
• Subjects: Cosmology and Nongalactic Astrophysics astro-ph.CO; Instrumentation and Methods for Astrophysics astro-ph.IM; FOS Physical sciences; Antarctic; Antarc*
• Online Access: https://dx.doi.org/10.48550/arxiv.1704.00215; https://arxiv.org/abs/1704.00215

We present a new upper limit on CMB circular polarization from the 2015 flight of SPIDER, a balloon-borne telescope designed to search for $B$-mode linear polarization from cosmic inflation. Although the level of circular polarization in the CMB is predicted to be very small, experimental limits provide a valuable test of the underlying models. By exploiting the non-zero circular-to-linear polarization coupling of the HWP polarization modulators, data from SPIDER's 2015 Antarctic flight provide a constraint on Stokes $V$ at 95 and 150 GHz from $33 : 9 pages, 4 figures, 5 tables - Updated to version accepted for publication in ApJ, modified acknowledgements