Decomposition of spectra from redshift distortion maps

Abstract

We develop an optimized technique to extract density-density and velocity-velocity spectra out of observed spectra in redshift space. The measured spectra of the distribution of haloes from redshift distorted mock map are binned into two-dimensional coordinates in Fourier space so as to be decomposed into both spectra using angular projection dependence. With the threshold limit introduced to minimize non-linear suppression, the decomposed velocity-velocity spectra are reasonably well measured up to scale k = 0.07 h Mpc-1, and the measured variances using our method are consistent with errors predicted from a Fisher matrix analysis. The detectability is extendable to k ∼ 0.1 h Mpc-1 with more conservative bounds at the cost of weakened constraint. © 2010 The Authors. Journal compilation © 2010 RAS.