Dark Energy Survey Year 1 results: measurement of the baryon acoustic oscillation scale in the distribution of galaxies to redshift 1

Abstract

We present angular diameter distance measurements obtained by locating the baryon acoustic oscillations (BAO) scale in the distribution of galaxies selected from the first year of Dark Energy Survey data. We consider a sample of over 1.3 million galaxies distributed over a footprint of 1336 deg2 with 0.6 < $z$photo < 1 and a typical redshift uncertainty of 0.03(1 + $z$). This sample was selected, as fully described in a companion paper, using a colour/magnitude selection that optimizes trade-offs between number density and redshift uncertainty. We investigate the BAO signal in the projected clustering using three conventions, the angular separation, the comoving transverse separation, and spherical harmonics. Further, we compare results obtained from template-based and machine-learning photometric redshift determinations. We use 1800 simulations that approximate our sample in order to produce covariance matrices and allow us to validate our distance scale measurement methodology. We measure the angular diameter distance, DA, at the effective redshift of our sample divided by the true physical scale of the BAO feature, rd. We obtain close to a 4 per cent distance measurement of DA($z$eff = 0.81)/rd = 10.75 ± 0.43. These results are consistent with the flat Λ cold dark matter concordance cosmological model supported by numerous other recent experimental results.

Implications of an extended dark energy cosmology with massive neutrinos for cosmological tensions

“…• BAO: We use measurements of the volume distance from 6dFGS at z = 0.106 [40] and the MGS galaxy sample of SDSS at z = 0.15 [41], as well as the recent DES1 BAO measurement at z = 0.81 [42]. We include the anisotropic measurements from the CMASS and LOWZ galaxy samples from the BOSS DR12 at z = 0.38, 0.51, and 0.61 [43].…”

Infrared resummation for biased tracers in redshift space

“…where D/Dτ is the convective derivative, 4) and in passing to the last equality we used that only the longitudinal component of the peculiar velocity is present in perturbation theory. The use of convective derivative accounts for the fact that the evolution of tracers is determined by the physical conditions along the fluid flow [71].…”

“…Baryon acoustic oscillations (BAO) are one of the most powerful tools of precision cosmology. The BAO pattern has been observed across various redshifts in the 2-point correlation function of the distribution of galaxies (see [1,2] for the first measurements and [3,4] for recent ones), Lyα forest absorption [5,6], quasars [7,8], and voids [9,10]. Recently, the BAO signal has also been detected in the 3point correlation function [11][12][13].…”

Observing the Dark Sector

“…We can see that DES data from the first year of observation is still not competitive with other data. The DES data also produced the measurement of what is called the shift parameter α which gives the location of the BAO peak with respect to a reference cosmology [Abbott et al, 2017i]. In Fig.…”

“…Measurement of the angular diameter distance from DES, compared to the Planck prediction and other measurements. From[Abbott et al, 2017i].Cluster selection function for the J-PAS survey 4293…”