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arXiv · 1901.03530

An estimation of the Local growth rate from Cosmicflows-3 peculiar velocities

A. Dupuy·H. M. Courtois·B. Kubik
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Abstract

This article explores three usual estimators, noted as $v_{12}$ of the pairwise velocity, $\psi_1$ and $\psi_2$ of the observed two-point galaxy peculiar velocity correlation functions. These estimators are tested on mock samples of {\it Cosmicflows-3} dataset \citep{Tully:2016aa} , derived from a numerical cosmological simulation, and also on a number of constrained realizations of this dataset. Observational measurements errors and cosmic variance are taken into consideration in the study. The result is a local measurement of $f \sigma_8 = 0.43 \left( \pm 0.03 \right)_\mathrm{obs} \left( \pm 0.11 \right)_\mathrm{cosmic}$ out to $z=0.05$, in support of a $\Lambda$CDM cosmology.

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A. Dupuy, H. M. Courtois, B. Kubik. 2019-01-11. An estimation of the Local growth rate from Cosmicflows-3 peculiar velocities. https://doi.org/10.1093/mnras%2Fstz901

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