Dark Energy Survey Year 3 Results: Deep Field Optical + Near-Infrared Images and Catalogue

Abstract

We describe the Dark Energy Survey (DES) Deep Fields, a set of images and associated multi-wavelength 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 $\sim 30$ square degrees in $ugriz$ bands and reaching a maximum $i$-band depth of 26.75 (AB, $10\sigma$, 2 arcsec). We present a catalogue for the DES 3-year cosmology analysis of those four fields with full 8-band coverage, totalling $5.88$ sq. deg. after masking. Numbering $2.8$million objects ($1.6$million post masking), our catalogue is drawn from images coadded to consistent depths of $r=25.7,i=25,z=24.3$ mag. We use a new model-fitting code, built upon established methods, to deblend sources and ensure consistent colours across the $u$-band to $Ks$-band wavelength range. We further detail the tight control we maintain over the point-spread function modelling required for the model fitting, astrometry and consistency of photometry between the four fields. The catalogue allows us to perform a careful star-galaxy separation and produces excellent photometric redshift performance ($\mathrm{NMAD}=0.023$ at $i<23$). The Deep-Fields catalogue will be made available as part of the cosmology data products release, following the completion of the DES 3-year weak lensing and galaxy clustering cosmology work.

32 pages, 23 figures, version accepted by MNRAS. See https://www.darkenergysurvey.org/des-year-3-cosmology-results-papers/ for the full DES Y3 cosmology release

References in corpus (32)

• The Gaia mission
• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• The Cosmic Evolution Survey (COSMOS) -- Overview
• EAZY: A Fast, Public Photometric Redshift Code
• zCOSMOS: A Large VLT/VIMOS redshift survey covering 0 < z < 3 in the COSMOS field
• Detection of quiescent galaxies in a bicolor sequence from z=0-2
• UltraVISTA: a new ultra-deep near-infrared survey in COSMOS
• UV Luminosity Functions at z~4, 5, and 6 from the HUDF and other Deep HST ACS Fields: Evolution and Star Formation History
• The MOSFIRE Deep Evolution Field (MOSDEF) Survey: Rest-Frame Optical Spectroscopy for ~1500 H-Selected Galaxies at 1.37 < z < 3.8
• Weak Gravitational Lensing with COSMOS: Galaxy Selection and Shape Measurements
• The VIMOS Ultra-Deep Survey: ~10,000 galaxies with spectroscopic redshifts to study galaxy assembly at early epochs 2<z<~6
• The fourth data release of the Kilo-Degree Survey: ugri imaging and nine-band optical-IR photometry over 1000 square degrees
• The Subaru/XMM-Newton Deep Survey (SXDS) - II. Optical Imaging and Photometric Catalogs
• Galaxy And Mass Assembly (GAMA): the G02 field, Herschel-ATLAS target selection and Data Release 3
• A lack of evolution in the very bright-end of the galaxy luminosity function from z = 8-10
• Photometric redshift analysis in the Dark Energy Survey Science Verification data
• The KMOS^3D Survey: data release and final survey paper
• The VISTA ZYJHKs Photometric System: Calibration from 2MASS
• The Complete Calibration of the Color-Redshift Relation (C3R2) Survey: Analysis and Data Release 2
• Euclid preparation: X. The Euclid photometric-redshift challenge
• Deconstructing the Galaxy Stellar Mass Function with UKIDSS and CANDELS: the Impact of Colour, Structure and Environment
• Forward Global Photometric Calibration of the Dark Energy Survey
• T-PHOT version 2.0: improved algorithms for background subtraction, local convolution, kernel registration, and new options
• OzDES multi-object fibre spectroscopy for the Dark Energy Survey: Results and second data release
• A Confirmation of the Strong Clustering of Distant Red Galaxies at 2 < z <3
• Number counts and clustering properties of bright Distant Red Galaxies in the UKIDSS Ultra Deep Survey Early Data Release
• The colour selection of distant galaxies in the UKIDSS Ultra-Deep Survey Early Data Release
• The impact of spectroscopic incompleteness in direct calibration of redshift distributions for weak lensing surveys
• High-velocity outflows in massive post-starburst galaxies at z > 1
• Environmental dependence of the galaxy stellar mass function in the Dark Energy Survey Science Verification Data
• Growing up in a megalopolis: Environmental effects on galaxy evolution in a supercluster at z~0.65 in UKIDSS UDS
• Exploring the High-Mass End of the Stellar Mass Function of Star Forming Galaxies at Cosmic Noon

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