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A Reanalysis of Small Scale Velocity Dispersion in the CfA1 Survey

Rachel S. Somerville·Marc Davis·Joel R. Primack
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Abstract

The velocity dispersion of galaxies on scales of $r\sim1h^{-1}$ Mpc, $σ_{12}(r)$, may be estimated from the anisotropy of the galaxy-galaxy correlation function in redshift space. We present a reanalysis of the CfA1 survey, correct an error in the original analysis of Davis and Peebles (1983), and find that $σ_{12}(r)$ is extremely sensitive to the details of how corrections for infall into the Virgo cluster are applied. We conclude that a robust value of $σ_{12}$ cannot be obtained from this survey. We also discuss results from other redshift surveys, including the effect of removing clusters.

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Rachel S. Somerville, Marc Davis, Joel R. Primack. 1996-04-09. A Reanalysis of Small Scale Velocity Dispersion in the CfA1 Survey. https://doi.org/10.1086/303899

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