Deriving accurate peculiar velocities (even at high redshift)

Abstract

The way that peculiar velocities are often inferred from measurements of distances and redshifts makes an approximation, v_p = cz-H_0 D, that gives significant errors even at relatively low redshifts (overestimates peculiar velocity by ~ 100 km/s at z~0.04). Here we demonstrate where the approximation breaks down, the systematic offset it introduces, and how the exact calculation should be implemented.

6 pages, 4 figures, accepted by MNRAS; revision adds footnote 3, a couple of references, and some minor tweaks to text

References in corpus (5)

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• SFI++ II: A New I-band Tully-Fisher Catalog, Derivation of Peculiar Velocities and Dataset Properties
• Current Status Of Velocity Field Surveys: A Consistency Check
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• An Unbiased Estimator of Peculiar Velocity with Gaussian Distributed Errors for Precision Cosmology
• Peculiar-velocity cosmology with Types Ia and II supernovae
• The Cosmic V-Web
• An accurate method to determine the systematics due to the peculiar velocities of galaxies in measuring the Hubble constant from gravitational wave standard sirens
• Local Hole revisited: evidence for bulk motions and self-consistent outflow
• Kerr black hole in de Sitter spacetime and observational redshift: Toward a new method to measure the Hubble constant
• From Cosmicflows distance moduli to unbiased distances and peculiar velocities
• MUSE-inspired view of the quasar Q2059-360, its Lyman alpha blob, and its neighborhood
• A general relativistic mass-to-distance ratio for a set of megamaser AGN black holes
• Shadow of Kottler black hole in the presence of plasma for a co-moving observer
• Measuring the velocity field from type Ia supernovae in an LSST-like sky survey