Information Content In The Galaxy Angular Power Spectrum From The Sloan Digital Sky Survey And Its Implication On Weak-lensing Analysis

摘要

We analyze the photometric redshift catalog of the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) to estimate the Fisher information in the galaxy angular power spectrum with the help of the Rimes-Hamilton technique. It is found that the amount of Fisher information contained in the galaxy angular power spectrum is saturated at lensing multipole scale 300 ≤ l ≤ 2000 in the redshift range 0.1 ≤ photo-z < 0.5. At l = 2000, the observed information is 2 orders of magnitude lower than the case of Gaussian fluctuations. This supports observationally that the translinear regime of the- density power spectrum contains little independent information about the initial cosmological conditions, which is consistent with the numerical trend shown by Rimes-Hamilton. Our results also suggest that the Gaussian-noise description-may not be valid in weak-lensing measurements.