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arXiv · 0705.1626

Phase analysis of the cosmic microwave background from an incomplete sky coverage

Lung-Yih Chiang·Pavel D. Naselsky
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Abstract

Phases of the spherical harmonic analysis of full-sky cosmic microwave background (CMB) temperature data contain useful information complementary to the ubiquitous angular power spectrum. In this letter we present a new method of phase analysis on incomplete sky maps. It is based on Fourier phases of equal-latitude pixel rings of the map, which are related to the mean angle of the trigonometric moments from the full-sky phases. They have an advantage for probing regions of interest without tapping polluted Galactic plane area, and can localize non-Gaussian features and departure from statistical isotropy in the CMB.

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Lung-Yih Chiang, Pavel D. Naselsky. 2007-06-14. Phase analysis of the cosmic microwave background from an incomplete sky coverage. https://doi.org/10.1111/j.1745-3933.2007.00352.x

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