The Dark Energy Survey Data Release 2

Abbott, T. M. C.; Adamow, M.; Aguena, M.; Allam, S.; Amon, A.; Annis, J.; Avila, S.; Bacon, D.; Banerji, M.; Bechtol, K.; Becker, M. R.; Bernstein, G. M.; Bertin, E.; Bhargava, S.; Bridle, S. L.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; Cawthon, R.; Chang, C.; Choi, A.; Conselice, C.; Costanzi, M.; Crocce, M.; Da Costa, L. N.; Davis, T. M.; De Vicente, J.; Derose, J.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Drlica-Wagner, A.; Eckert, K.; Elvin-Poole, J.; Everett, S.; Evrard, A. E.; Ferrero, I.; Ferte, A.; Flaugher, B.; Fosalba, P.; Friedel, D.; Frieman, J.; Garcia-Bellido, J.; Gaztanaga, E.; Gelman, L.; Gerdes, D. W.; Giannantonio, T.; Gill, M. S. S.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Hartley, W. G.; Hinton, S. R.; Hollowood, D. L.; Honscheid, K.; Huterer, D.; James, D. J.; Jeltema, T.; Johnson, M. D.; Kent, S.; Kron, R.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; T. S., Li; Lidman, C.; Lin, H.; Maccrann, N.; Maia, M. A. G.; Manning, T. A.; Maloney, J. D.; March, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Menanteau, F.; Miquel, R.; Morgan, R.; Myles, J.; Neilsen, E.; Ogando, R. L. C.; Palmese, A.; Paz-Chinchon, F.; Petravick, D.; Pieres, A.; Plazas, A. A.; Pond, C.; Rodriguez-Monroy, M.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sako, M.; Sanchez, E.; Santiago, B.; Scarpine, V.; Serrano, S.; Sevilla-Noarbe, I.; Smith, J. A.; Smith, M.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; To, C.; Tremblay, P. E.; Troxel, M. A.; Tucker, D. L.; Turner, D. J.; Varga, T. N.; Walker, A. R.; Wechsler, R. H.; Weller, J.; Wester, W.; Wilkinson, R. D.; Yanny, B.; Zhang, Y.; Nikutta, R.; Fitzpatrick, M.; Jacques, A.; Scott, A.; Olsen, K.; Huang, L.; Herrera, D.; Juneau, S.; Nidever, D.; Weaver, B. A.; Adean, C.; Correia, V.; De Freitas, M.; Freitas, F. N.; Singulani, C.; Vila-Verde, G.

doi:10.3847/1538-4365/ac00b3

We present the second public data release of the Dark Energy Survey, DES DR2, based on optical/near-infrared imaging by the Dark Energy Camera mounted on the 4 m Blanco telescope at Cerro Tololo Inter-American Observatory in Chile. DES DR2 consists of reduced single-epoch and coadded images, a source catalog derived from coadded images, and associated data products assembled from 6 yr of DES science operations. This release includes data from the DES wide-area survey covering ∼5000 deg2 of the southern Galactic cap in five broad photometric bands, grizY. DES DR2 has a median delivered point-spread function FWHM of g = 1.11″, r = 0.95″, i = 0.88″, z = 0.83″, and Y = 0.″90, photometric uniformity with a standard deviation of < 3 mmag with respect to Gaia DR2 G band, a photometric accuracy of ∼11 mmag, and a median internal astrometric precision of ∼27 mas. The median coadded catalog depth for a 1.″95 diameter aperture at signal-to-noise ratio = 10 is g = 24.7, r = 24.4, i = 23.8, z = 23.1, and Y = 21.7 mag. DES DR2 includes ∼691 million distinct astronomical objects detected in 10,169 coadded image tiles of size 0.534 deg2 produced from 76,217 single-epoch images. After a basic quality selection, benchmark galaxy and stellar samples contain 543 million and 145 million objects, respectively. These data are accessible through several interfaces, including interactive image visualization tools, web-based query clients, image cutout servers, and Jupyter notebooks. DES DR2 constitutes the largest photometric data set to date at the achieved depth and photometric precision.