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A Remark on the Estimation of Angular Power Spectra in the Presence of Foregrounds

Martin White
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Abstract

It is common practice to estimate the errors on the angular power spectrum which could be obtained by an experiment with a given angular resolution and noise level. Several authors have also addressed the question of foreground subtraction using multi-frequency observations. In such observations the angular resolution of the different frequency channels is rarely the same. In this report we point out how the ``effective'' beam size and noise level change with ell in this case, and give an expression for the error on the angular power spectrum as a function of ell.

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Martin White. 1998-02-16. A Remark on the Estimation of Angular Power Spectra in the Presence of Foregrounds. https://doi.org/10.1103/physrevd.57.5273

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