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arXiv · 1211.5213

A Robust Measure of Cosmic Structure beyond the Power-Spectrum: Cosmic Filaments and the Temperature of Dark Matter

Danail Obreschkow·Chris Power·Martin Bruderer·Camille Bonvin
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Abstract

We discover that the mass of dark matter particles mDM is imprinted in phase-correlations of the cosmic density field more significantly than in the 2-point correlation. In particular, phase-correlations trace mDM out to scales about five times larger than the 2-point correlation. This result relies on a new estimator l(r) of pure phase-information in Fourier space, which can be interpreted as a parameter-free and scale-invariant tracer of filament-like structure. Based on simulated density fields we show how mDM can, in principle, be measured using l(r), given a suitably reconstructed density field.

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Danail Obreschkow, Chris Power, Martin Bruderer, Camille Bonvin. 2012-12-18. A Robust Measure of Cosmic Structure beyond the Power-Spectrum: Cosmic Filaments and the Temperature of Dark Matter. https://doi.org/10.1088/0004-637x%2F762%2F2%2F115

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