Dark Energy Survey: 2.1% measurement of the Baryon Acoustic Oscillation scale from the final dataset

TL;DR

This paper reports a highly precise measurement of the BAO scale from the Dark Energy Survey data, providing important constraints on cosmology and testing Planck predictions at high redshift.

Contribution

It presents the most precise photometric BAO measurement at high redshift, using DES data, and demonstrates robustness against systematics.

Findings

Measured $D_M(z_{eff})/r_d$ = 19.51 ± 0.41

Result is 2.13σ below Planck predictions

Achieved the most precise high-redshift BAO measurement from photometric data

Abstract

Here, we present the angular diameter distance measurement obtained from the measurement of the Baryonic Acoustic Oscillation (BAO) feature using the completed Dark Energy Survey (DES) data, summarizing the main results of [Phys. Rev. D 110, 063514] and [Phys. Rev. D 110, 063515]. We use a galaxy sample optimized for BAO science in the redshift range 0.6 < z < 1.2, with an effective redshift of $z_{\rm eff}$ = 0.85. Our consensus measurement constrains the ratio of the angular distance to the sound horizon scale to $D_M(z_{\rm eff})/r_d$ = 19.51 $\pm$ 0.41. This measurement is found to be 2.13$\sigma$ below the angular BAO scale predicted by Planck. To date, it represents the most precise measurement from purely photometric data, and the most precise from any Stage-III experiment at such high redshift. The analysis was performed blinded to the BAO position and is shown to be robust against analysis choices, data removal, redshift calibrations and observational systematics.