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arXiv · 1012.3750

ISW Imprint of Superstructures on Linear Scales

Péter Pápai·István Szapudi·Ben R Granett
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Abstract

We build a model for the density and integrated Sachs-Wolfe (ISW) profile of supervoid and supercluster structures. Our model assumes that fluctuations evolve linearly from an initial Gaussian random field. We find these assumptions capable of describing N-body simulations and simulated ISW maps remarkably well on large scales. We construct an ISW map based on locations of superstructures identified previously in the SDSS Luminous Red Galaxy sample. A matched filter analysis of the cosmic microwave background confirms a signal at the $3.2-σ$ confidence level and estimates the radius of the underlying structures to be $55 \pm 28 ~h^{-1}$Mpc. The amplitude of the signal, however, is $2-σ$ higher than $Λ$CDM predictions.

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Péter Pápai, István Szapudi, Ben R Granett. 2010-12-16. ISW Imprint of Superstructures on Linear Scales. https://doi.org/10.1088/0004-637x%2F732%2F1%2F27

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