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arXiv · astro-ph/0107013

A Limit on the Large Angular Scale Polarization of the Cosmic Microwave Background

Abstract

We present an upper limit on the polarization of the Cosmic Microwave Background at 7 degree angular scales in the frequency band between 26 and 36 GHz, produced by the POLAR experiment. The campaign produced a map of linear polarization over the R.A. range 112 degrees - 275 degrees at declination 43degrees. The model-independent upper limit on the E-mode polarization component of the CMB at angular scales l = 2 - 20 is 10 microKelvin (95% confidence). The corresponding limit for the B-mode is also 10 microKelvin. Constraining the B-mode power to be zero, the 95% confidence limit on E-mode power alone is 8 microKelvin.

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Brian G. Keating, Christopher W. O'Dell, Angelica de Oliveira-Costa, Slade Klawikowski, Nate Stebor, Lucio Piccirillo, Max Tegmark, Peter T. Timbie. 2001-07-02. A Limit on the Large Angular Scale Polarization of the Cosmic Microwave Background. https://doi.org/10.1086/324222

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