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An estimate of Ω_m without priors

Hume A. Feldman·Roman Juszkiewicz·Pedro Ferreira·Marc Davis·Enrique Gaztanaga·James N. Fry·Andrew Jaffe·Scott W. Chambers·Luiz da Costa·Mariangela Bernardi·Riccardo Giovanelli·Martha P. Haynes·Gary Wegner
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Abstract

Using mean relative peculiar velocity measurements for pairs of galaxies, we estimate the cosmological density parameter $Ω_m$ and the amplitude of density fluctuations $σ_8$. Our results suggest that our statistic is a robust and reproducible measure of the mean pairwise velocity and thereby the $Ω_m$ parameter. We get $Ω_m = 0.30^{+0.17}_{-0.07}$ and $σ_8 = 1.13^{+0.22}_{-0.23}$. These estimates do not depend on prior assumptions on the adiabaticity of the initial density fluctuations, the ionization history, or the values of other cosmological parameters.

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Hume A. Feldman, Roman Juszkiewicz, Pedro Ferreira, Marc Davis, Enrique Gaztanaga, James N. Fry, Andrew Jaffe, Scott W. Chambers, Luiz da Costa, Mariangela Bernardi, Riccardo Giovanelli, Martha P. Haynes, Gary Wegner. 2003-10-17. An estimate of Ω_m without priors. https://doi.org/10.1086/379221

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