Deriving accurate peculiar velocities (even at high redshift)
Cosmology and Nongalactic Astrophysics
2015-06-19 v2
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.
Cite
@article{arxiv.1405.0105,
title = {Deriving accurate peculiar velocities (even at high redshift)},
author = {Tamara M. Davis and Morag I. Scrimgeour},
journal= {arXiv preprint arXiv:1405.0105},
year = {2015}
}
Comments
6 pages, 4 figures, accepted by MNRAS; revision adds footnote 3, a couple of references, and some minor tweaks to text