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arXiv · astro-ph/0205438

Using Galaxy Cluster Peculiar Velocities to Constrain Cosmological Parameters

A. Peel·L. Knox
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Abstract

Galaxy cluster peculiar velocities can be inferred from high-sensitivity, high-resolution multiple-frequency observations in the 30 to 400 GHz range. While galaxy cluster counts and power spectra are sensitive to the growth factor, peculiar velocities are sensitive to the time-derivative of the growth factor and are hence complementary. Using linear perturbation theory, we forecast constraints on Omega(matter), the Hubble constant today, and the dark-energy equation of state parameter, given 820 densely sampled cluster locations (near redshift 1) from a Lambda-CDM N-body simulation and 820 sparsely sampled cluster locations in a broader redshift range.

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A. Peel, L. Knox. 2002-05-24. Using Galaxy Cluster Peculiar Velocities to Constrain Cosmological Parameters. https://doi.org/10.1016/s0920-5632(03)02083-8

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