The anisotropic redshift space galaxy correlation function: detection on the BAO Ring

TL;DR

This paper reports the detection of a circular BAO ring in the galaxy correlation function from SDSS data, supporting current cosmological models of large-scale structure formation.

Contribution

It presents the first significant detection of a BAO ring in the anisotropic galaxy correlation function using SDSS LRG data, with validation from mock simulations.

Findings

Detection of a BAO ring at ~110 Mpc/h

Shape and position consistent with BAO predictions

Supports current models of large-scale structure formation

Abstract

In a series of papers we have recently studied the clustering of LRG galaxies in the latest spectroscopic SDSS data release, which has 75000 LRG galaxies sampling 1.1 Gpc^3/h^3 to z=0.47. Here we focus on detecting a local maxima shaped as a circular ring in the bidimensional galaxy correlation function \xi(pi,sigma), separated in perpendicular \sigma and line-of-sight \pi distances. We find a significant detection of such a peak at r ~110 Mpc/h. The overall shape and location of the ring is consistent with it originating from the recombination-epoch baryon acoustic oscillations (BAO). This agreement provides support for the current understanding of how large scale structure forms in the universe. We study the significance of such feature using large mock galaxy simulations to provide accurate errorbars.