Power spectrum of the maxBCG cluster sample: new evidence for the acoustic features
Abstract
Description
We use the direct Fourier method to calculate the redshift-space power spectrum of the maxBCG cluster catalog (Koester et al. 2007) -- currently by far the largest existing galaxy cluster sample. The total number of clusters used in our analysis is 12,616. After accounting for the radial smearing effect caused by photometric redshift errors and also introducing a simple treatment for the nonlinear effects, we show that currently favored low matter density ``concordance'' LambdaCDM cosmology provides a very good fit to the estimated power. Thanks to the large volume (~ 0.4 h^{-3} Gpc^3), high clustering amplitude (linear effective bias parameter b_{eff} ~ 3x(0.85/sigma_8)), and sufficiently high sampling density (~ 3x10^{-5} h^{3} Mpc^{-3}) the recovered power spectrum has high enough signal to noise to allow us to find weak evidence (~ 2sigma CL) for the acoustic features. These results are encouraging in light of the several proposed large cluster surveys. In case we use the photometric redshift errors as suggested in Koester et al. (2007) we are left with the excess large-scale power which has previously been noticed by several other authors.
10 pages, submitted to MNRAS
10 pages, submitted to MNRAS