On the effect of baryon-CDM streaming velocity on the clustering of galaxies
Year: 2016
Type: preprint
Abstract: Pre-recombination acoustic oscillations induce an initial relative velocity $v_{cb}$ between baryons and dark matter. We show that the leading effect on galaxy clustering at lower redshifts is induced by its divergence $\theta_{cb} = \partial_i v_{cb}^i$, and estimate the magnitude of this new effect through a spherical collapse calculation. We then derive all streaming velocity contributions to the galaxy power spectrum at 1-loop order, leading to several new terms. Including all these contributions will be essential to avoid a bias in future efforts to use the baryon acoustic oscillation feature in galaxy clustering as standard ruler.
Source: arXiv (Cornell University)
Author: Fabian Schmidt
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2290226239