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New Limits on the Polarized Anisotropy of the Cosmic Microwave Background at Subdegree Angular Scales

M. M. Hedman·D. Barkats·J. O. Gundersen·J. J. McMahon·S. T. Staggs·B. Winstein
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Abstract

We update the limit from the 90 GHz PIQUE ground-based polarimeter on the magnitude of any polarized anisotropy of the cosmic microwave radiation. With a second year of data, we have now limited both Q and U on a ring of 1 degree radius. The window functions are broad: for E-mode polarization, the effective l is = 191 +143 -132. We find that the E-mode signal can be no greater than 8.4 microK (95% CL), assuming no B-mode polarization. Limits on a possible B-mode signal are also presented.

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M. M. Hedman, D. Barkats, J. O. Gundersen, J. J. McMahon, S. T. Staggs, B. Winstein. 2002-04-25. New Limits on the Polarized Anisotropy of the Cosmic Microwave Background at Subdegree Angular Scales. https://doi.org/10.1086/342020

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