Overview of the DESI Legacy Imaging Surveys


Dey A, Schlegel DJ, Lang D, Blum R, Burleigh K, Fan X, Findlay JR, Finkbeiner D, Herrera D, Juneau S, et al. Overview of the DESI Legacy Imaging Surveys. The Astronomical Journal [Internet]. 2019;157.

Date Published:

May 01, 2019


The DESI Legacy Imaging Surveys (http://legacysurvey.org/) are acombination of three public projects (the Dark Energy Camera LegacySurvey, the Beijing-Arizona Sky Survey, and the Mayall z-band LegacySurvey) that will jointly image ≈14,000 deg2 of theextragalactic sky visible from the northern hemisphere in three opticalbands (g, r, and z) using telescopes at the Kitt Peak NationalObservatory and the Cerro Tololo Inter-American Observatory. Thecombined survey footprint is split into two contiguous areas by theGalactic plane. The optical imaging is conducted using a unique strategyof dynamically adjusting the exposure times and pointing selectionduring observing that results in a survey of nearly uniform depth. Inaddition to calibrated images, the project is delivering a catalog,constructed by using a probabilistic inference-based approach toestimate source shapes and brightnesses. The catalog includes photometryfrom the grz optical bands and from four mid-infrared bands (at 3.4,4.6, 12, and 22 μm) observed by the Wide-field Infrared Survey Explorersatellite during its full operational lifetime. The project plans twopublic data releases each year. All the software used to generate thecatalogs is also released with the data. This paper provides an overviewof the Legacy Surveys project.