1999/04/06 by Pedro G. Ferreira, M. Davis, Ferreira, P. G. +7 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Scientific Research and Discoveries
paper · pdf · doi:10.48550/arxiv.astro-ph/9904074
openalex publication_date 1999/04/06 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The mean pairwise velocity of galaxies has traditionally been estimated from the redshift space galaxy correlation function. This method is notorious for being highly sensitive to the assumed model of the pairwise velocity dispersion. Here we propose an alternative method to estimate the streaming velocity directly from peculiar velocity samples, which contain redshift-independent distances as well as galaxy redshifts. This method can provide an estimate of Ω0.6σ82 for a range of σ8 where Ω is the cosmological density parameter, while σ8 is the standard normalization for the power spectrum of density fluctuations. We demonstrate how to measure this quantity from realistic catalogues and identify the main sources of bias and errors