http://arxiv.org/abs/1801.04969
The peculiar velocities of galaxies cause their redshift-space clustering to depend on the angle to the line-of-sight, providing a key test of gravitational physics on cosmological scales. These effects may be described using a multipole expansion of the clustering measurements. Focussing on Fourier-space statistics, we present a new analysis of the effect of the survey window function, and the variation of the line-of-sight across a survey, on the modelling of power spectrum multipoles. We determine the joint covariance of the Fourier-space multipoles in a Gaussian approximation, and indicate how these techniques may be extended to studies of overlapping galaxy populations via multipole cross-power spectra. We apply our methodology to one of the widest-area galaxy redshift surveys currently available, the 6-degree Field Galaxy Survey, deducing a normalized growth rate f*sigma_8 = 0.38 +/- 0.12 in the low-redshift Universe, in agreement with previous analyses of this dataset using different techniques. Our framework should be useful for processing future wide-angle galaxy redshift surveys.
C. Blake, P. Carter and J. Koda
Wed, 17 Jan 18
28/51
Comments: 15 pages, 7 figures, submitted to MNRAS, comments welcome