Fisher matrix forecast on cosmological parameters from the dark energy survey 2-point angular correlation function

Full text: We study the cosmological constraints expected for the upcoming project Dark Energy Survey (DES) with the full functional form of the 2-point angular correlation function. The angular correlation function model applied in this work includes the effects of linear redshift-space distortion, photometric redshift errors (assumed to be Gaussian) and non-linearities prevenient from gravitational infall. The Fisher information matrix is constructed with the full covariance matrix, which takes the correlation between nearby redshift shells in a proper manner. The survey was sliced into 20 redshift shells in the range 0:4 ≤ z ≤ 1:40 with a variable angular scale in order to search only the scale around the signal from the baryon acoustic oscillation, therefore well within the validity of the non-linear model employed. We found that under those assumptions and with a flat ΛCDM WMAP7 fiducial model, the DES will be able to constrain the dark energy equation of state parameter w with a precision of ∼ 20% and the cold dark matter with ∼ 11% when marginalizing over the other 25 parameters (bias is treated as a free parameter for each shell). When applying WMAP7 priors on Ωbaryon, Ω cdm, ns, and HST priors on the Hubble parameter, w is constrained with ∼ 9% precision. This shows that the full shape of the angular correlation function with DES data will be a powerful probe to constrain cosmological parameters. (author)