Baryon Acoustic Oscillations from the SDSS DR10 galaxies angular correlation function

TL;DR

This study measures the angular BAO signal from SDSS DR10 galaxies using the 2-point angular correlation function, providing constraints on dark energy models with minimal model dependence.

Contribution

It presents a model-independent method to estimate BAO angular scales from galaxy data and discusses systematic effects affecting the measurement.

Findings

BAO angular scale measurements are consistent with the $ m{ extLambda CDM}$ model.

Constraints on dark energy parameters are derived from the $ heta_{ m{BAO}}(z)$ data.

The analysis confirms the compatibility of standard cosmological models with observational data.

Abstract

The 2-point angular correlation function $w(\theta)$ (2PACF), where $\theta$ is the angular separation between pairs of galaxies, provides the transversal Baryon Acoustic Oscillation (BAO) signal almost model-independently. In this paper we use 409,337 luminous red galaxies in the redshift range $z = [0.440,0.555]$ obtained from the tenth data release of the Sloan Digital Sky Survey (SDSS DR10) to estimate $\theta_{\rm{BAO}}(z)$ from the 2PACF at six redshift {shells}. Since noise and systematics can hide the BAO signature in the $w - \theta$ plane, we also discuss some criteria to localize the acoustic bump. We identify two sources of model-dependence in the analysis, namely, the value of the acoustic scale from Cosmic Microwave Background (CMB) measurements and the correction in the $\theta_{\rm{BAO}}(z)$ position due to projection effects. Constraints on the dark energy equation-of-state parameter w$(z)$ from the $\theta_{\rm{BAO}}(z)$ diagram are derived, as well as from a joint analysis with current CMB measurements. We find that the standard $\Lambda$CDM model as well as some of its extensions are in good agreement with these $\theta_{\rm{BAO}}(z)$ measurements.