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Decorrelating the Power Spectrum of Galaxies

A. J. S. Hamilton·Max Tegmark
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Abstract

It is shown how to decorrelate the (prewhitened) power spectrum measured from a galaxy survey into a set of high resolution uncorrelated band-powers. The treatment includes nonlinearity, but not redshift distortions. Amongst the infinitely many possible decorrelation matrices, the square root of the Fisher matrix, or a scaled version thereof, offers a particularly good choice, in the sense that the band-power windows are narrow, approximately symmetric, and well-behaved in the presence of noise. We use this method to compute band-power windows for, and the information content of, the Sloan Digital Sky Survey, the Las Campanas Redshift Survey, and the IRAS 1.2 Jy Survey.

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A. J. S. Hamilton, Max Tegmark. 2000-03-15. Decorrelating the Power Spectrum of Galaxies. https://doi.org/10.1046/j.1365-8711.2000.03074.x

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