Optimizing the recovery of Fisher information in the dark matter power spectrum

• Published in: Monthly notices of the Royal Astronomical Society 2013-11, Vol.436 (1), p.759-773
• Main Authors: Harnois-Déraps, Joachim, Yu, Hao-Ran, Zhang, Tong-Jie, Pen, Ue-Li
• Format: Article
• Language: English
• Subjects: Algorithms; Comparative analysis; Dark matter; Measurement; Probability distribution; Star & galaxy formation
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stt1611

We examine and combine different techniques that are known to increase the Fisher information content about the amplitude of the matter power spectrum, and propagate their impact on a baryonic acoustic oscillation (BAO) measurement. We compare a density reconstruction algorithm based on Zel'dovich displacement fields, a wavelet non-linear Wiener filter, a direct Gaussianization of the probability distribution function of the wavelet function coefficients and the action of the last two techniques on the first one. From a series of 200 N-body simulations, we compute the Fisher information and quantify the recovery performance, both using dark matter particles and haloes. We find that the height of the Fisher information trans-linear plateau is generally increased by the various techniques, by up to an order of magnitude at k = 0.6 h Mpc−1; however, shot noise subtracted halo measurements exhibit a milder information recovery. When we perform a BAO measurement from these altered density fields, we find that the reconstruction technique is the only one that sharpens the peak; the two wavelet-based techniques in fact smear out the features, thus reducing the overall precision of the cosmological ladder. We examine in detail why this occurs even though their Fisher information increased.