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arXiv · 1009.0754

Cosmological Density Fluctuations on 100Mpc Scales and their ISW Effect

Péter Pápai·István Szapudi
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Abstract

We measure the matter probability distribution function (PDF) via counts in cells in a volume limited subsample of the Sloan Digital Sky Survey Luminous Red Galaxy Catalog on scales from $30 h^{-1}$Mpc to $150 h^{-1}$Mpc and estimate the linear Integrated Sachs--Wolfe effect produced by supervoids and superclusters in the tail of the PDF. We characterize the PDF by the variance, $S_3$, and $S_4$, and study in simulations the systematic effects due to finite volume, survey shape and redshift distortion. We compare our measurement to the prediction of $Λ$CDM with linear bias and find a good agreement. We use the moments to approximate the tail of the PDF with analytic functions. A simple Gaussian model for the superstructures appears to be consistent with the claim by Granett et al. that density fluctuations on $100 h^{-1}$Mpc scales produce hot and cold spots with $ΔT \approx 10μK$ on the cosmic microwave background.

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Péter Pápai, István Szapudi. 2010-12-15. Cosmological Density Fluctuations on 100Mpc Scales and their ISW Effect. https://doi.org/10.1088/0004-637x%2F725%2F2%2F2078

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