Scale-Dependent Bias of Galaxies from Baryonic Acoustic Oscillations

TL;DR

This paper discusses how baryonic acoustic oscillations induce a scale-dependent bias in galaxy distribution relative to dark matter, which can help calibrate galaxy mass-to-light ratios without significantly impacting BAO measurements.

Contribution

It introduces the concept of a scale-dependent galaxy bias caused by BAOs and suggests its potential use in calibrating galaxy mass-to-light ratios based on baryon mass fraction.

Findings

Bias oscillates with scale due to BAOs

Measurement can calibrate galaxy mass-to-light ratio dependence

Bias unlikely to affect BAO peak position measurements

Abstract

Baryonic acoustic oscillations (BAOs) modulate the density ratio of baryons to dark matter across large regions of the Universe. We show that the associated variation in the mass-to-light ratio of galaxies should generate an oscillatory, scale-dependent bias of galaxies relative to the underlying distribution of dark matter. A measurement of this effect would calibrate the dependence of the characteristic mass-to-light ratio of galaxies on the baryon mass fraction in their large scale environment. This bias, though, is unlikely to significantly affect measurements of BAO peak positions.