We describe the Dark Energy Survey (DES) Deep Fields, a set of images and associated multiwavelength catalogue (ugrizJHKs) built from Dark Energy Camera (DECam) and Visible and Infrared Survey Telescope for Astronomy (VISTA) data. The DES Deep Fields comprise 11 fields (10 DES supernova fields plus COSMOS), with a total area of ~30 sq. deg. in

This work and its companion paper, Amon et al. [Phys. Rev. D 105, 023514 (2022), 10.1103/PhysRevD.105.023514], present cosmic shear measurements and cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrain the lensing amplitude parameter S 8≡σ 8√{Ω m/0.3 } at the 3% level in Λ CDM : S

This work, together with its companion paper, Secco, Samuroff et al. [Phys. Rev. D 105, 023515 (2022), 10.1103/PhysRevD.105.023515], present the Dark Energy Survey Year 3 cosmic-shear measurements and cosmological constraints based on an

We present the first cosmology results from large-scale structure using the full 5000 deg 2 of imaging data from the Dark Energy Survey (DES) Data Release 1. We perform an analysis of large-scale structure combining three two-point correlation functions (3 ×2 pt ): (i) cosmic shear using 100 million source galaxies, (ii) galaxy clustering, and (iii

As the statistical power of galaxy weak lensing reaches per cent level precision, large, realistic, and robust simulations are required to calibrate observational systematics, especially given the increased importance of object blending as survey depths increase. To capture the coupled effects of blending in both shear and photometric redshift

A30 belongs to a class of planetary nebulae identified as "born-again", containing dense, hydrogen-poor ejecta with extreme abundance discrepancy factors (ADFs), likely associated with a central binary system. We present intermediate-dispersion spectroscopy of one such feature-the J4 equatorial knot. We confirm the apparent physical and chemical