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arXiv · 1405.0105

Deriving accurate peculiar velocities (even at high redshift)

Tamara M. Davis·Morag I. Scrimgeour
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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.

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Tamara M. Davis, Morag I. Scrimgeour. 2014-05-27. Deriving accurate peculiar velocities (even at high redshift). https://doi.org/10.1093/mnras%2Fstu920

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