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First attempt at measuring the CMB cross-polarization

Angelica de Oliveira-Costa·Max Tegmark·Matias Zaldarriaga·Denis Barkats·Josh O. Gundersen·Matt M. Hedman·Suzanne T. Staggs·Bruce Winstein
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Abstract

We compute upper limits on CMB cross-polarization by cross-correlating the PIQUE and Saskatoon experiments. We also discuss theoretical and practical issues relevant to measuring cross-polarization and illustrate them with simulations of the upcoming BOOMERanG 2002 experiment. We present a method that separates all six polarization power spectra (TT, EE, BB, TE, TB, EB) without any other "leakage" than the familiar EE-BB mixing caused by incomplete sky coverage. Since E and B get mixed, one might expect leakage between TE and TB, between EE and EB and between BB and EB - our method eliminates this by preserving the parity symmetry under which TB and EB are odd and the other four power spectra are even.

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Angelica de Oliveira-Costa, Max Tegmark, Matias Zaldarriaga, Denis Barkats, Josh O. Gundersen, Matt M. Hedman, Suzanne T. Staggs, Bruce Winstein. 2002-04-02. First attempt at measuring the CMB cross-polarization. https://doi.org/10.1103/physrevd.67.023003

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