Improving reconstruction of the baryon acoustic peak : the effect of local environment

TL;DR

This paper investigates how local environment affects the accuracy of density-field reconstruction for sharpening the BAO peak, proposing improved methods using environmental re-weighting and higher-order perturbation theory.

Contribution

It demonstrates the environmental dependence of the Zel'dovitch approximation and introduces enhanced BAO measurement techniques incorporating local environment information.

Findings

Accuracy of Zel'dovitch approximation varies with environment

Environmental re-weighting improves BAO peak sharpening

Higher-order perturbation theory enhances displacement field estimates

Abstract

Precise measurements of the baryon acoustic oscillation (BAO) scale as a standard ruler in the clustering pattern of large-scale structure is a central goal of current and future galaxy surveys. The BAO peak may be sharpened using the technique of density-field reconstruction, in which the bulk displacements of galaxies are estimated using a Zel'dovitch approximation. We use numerical simulations to demonstrate how the accuracy of this approximation depends strongly on local environment, and how this information may be used to construct an improved BAO measurement through environmental re-weighting and using higher-order perturbation theory. We outline further applications of the displacement field for testing cosmological models.