Coherent Combination of Baryon Acoustic Oscillation Statistics and Peculiar Velocity Measurements from Redshift Survey

TL;DR

This paper introduces a new statistical method that combines BAO and peculiar velocity data from redshift surveys to improve dark energy constraints and cross-validate results, avoiding galaxy bias uncertainties.

Contribution

The paper presents a novel approach to coherently combine BAO and velocity measurements using decomposed spectra, enhancing dark energy constraints and eliminating galaxy bias assumptions.

Findings

Dark energy constraints improved to .06 and 0.20.

Method is free from galaxy bias uncertainties.

Provides a consistency check between two cosmological probes.

Abstract

New statistical method is proposed to coherently combine Baryon Acoustic Oscillation statistics (BAO) and peculiar velocity measurements exploiting decomposed density-density and velocity-velocity spectra in real space from the observed redshift distortions in redshift space, 1) to achieve stronger dark energy constraints, \sigma(w)=0.06 and \sigma(w_a)=0.20, which are enhanced from BAO or velocity measurements alone, and 2) to cross-check consistency of dark energy constraints from two different approaches; BAO as geometrical measurements and peculiar velocity as large scale structure formation observables. In addition to those advantages, as power spectra decomposition procedure is free from uncertainty of galaxy bias, this simultaneous fitting is an optimal method to extract cosmological parameters without any pre-assumption about galaxy bias.