The Three‐Dimensional Power Spectrum of Galaxies from the Sloan Digital Sky Survey

Abstract

We measure the large-scale real-space power spectrum P(k) using a sample of\n205,443 galaxies from the Sloan Digital Sky Survey, covering 2417 square\ndegrees with mean redshift z~0.1. We employ a matrix-based method using\npseudo-Karhunen-Loeve eigenmodes, producing uncorrelated minimum-variance\nmeasurements in 22 k-bands of both the clustering power and its anisotropy due\nto redshift-space distortions, with narrow and well-behaved window functions in\nthe range 0.02 h/Mpc < k < 0.3h/Mpc. We pay particular attention to modeling,\nquantifying and correcting for potential systematic errors, nonlinear redshift\ndistortions and the artificial red-tilt caused by luminosity-dependent bias.\nOur final result is a measurement of the real-space matter power spectrum P(k)\nup to an unknown overall multiplicative bias factor. Our calculations suggest\nthat this bias factor is independent of scale to better than a few percent for\nk<0.1h/Mpc, thereby making our results useful for precision measurements of\ncosmological parameters in conjunction with data from other experiments such as\nthe WMAP satellite. As a simple characterization of the data, our measurements\nare well fit by a flat scale-invariant adiabatic cosmological model with h\nOmega_m =0.201+/- 0.017 and L* galaxy sigma_8=0.89 +/- 0.02 when fixing the\nbaryon fraction Omega_b/Omega_m=0.17 and the Hubble parameter h=0.72;\ncosmological interpretation is given in a companion paper.\n