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Publication

Dark Energy Survey Year 3 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing

Authors

Abbott, T. M. C.; Aguena, M. ; Alarcon, A.; Allam, S. ; Alves, O.; Amon, A.; Andrade-Oliveira, F.; Annis, J.; Avila, S.; Bacon, D.; Becker, M. R.

Abstract

We present the first cosmology results from large-scale structure in the Dark Energy Survey (DES) spanning 5000 deg2. We perform an analysis combining three two-point correlation functions (32pt): (i) cosmic shear using 100 million source galaxies, (ii) galaxy clustering, and (iii) the cross-correlation of source galaxy shear with lens galaxy positions. The analysis was designed to mitigate confirmation or observer bias; we describe specific changes made to the lens galaxy sample following unblinding of the results. We model the data within the flat CDM and wCDM cosmological models. We find consistent cosmological results between the three two-point correlation functions; their combination yields clustering amplitude S8=0.776+0.0170.017 and matter density m=0.339+0.0320.031 in CDM, mean with 68% confidence limits; S8=0.775+0.0260.024, m=0.352+0.0350.041, and dark energy equation-of-state parameter w=0.98+0.320.20 in wCDM. This combination of DES data is consistent with the prediction of the model favored by the Planck 2018 cosmic microwave background (CMB) primary anisotropy data, which is quantified with a probability-to-exceed p=0.13 to 0.48. When combining DES 32pt data with available baryon acoustic oscillation, redshift-space distortion, and type Ia supernovae data, we find p=0.34. Combining all of these data sets with Planck CMB lensing yields joint parameter constraints of S8=0.812+0.0080.008, m=0.306+0.0040.005, h=0.680+0.0040.003, and m<0.13eV(95%CL) in CDM; S8=0.812+0.0080.008, m=0.302+0.0060.006, h=0.687+0.0060.007, and w=1.031+0.0300.027 in wCDM. (abridged)