Target Selection for the SDSS-IV APOGEE-2 Survey
Poleski, R.; Mészáros, Sz.; Covey, K.; Johnson, J. A.; Dell'Agli, F.; Cohen, R. E.; Cunha, K.; Majewski, S. R.; García-Hernández, D. A.; Muñoz, R. R.; Nidever, D. L.; Fleming, Scott W.; Stringfellow, G. S.; Simon, J. D.; Bovy, J.; Smith, V. V.; Tayar, J.; Shetrone, M.; Bird, J. C.; Chojnowski, S. D.; Santana, F.; Holtzman, J.; Zasowski, G.; Beaton, R. L.; Ness, M. K.; Harding, P.; Kollmeier, J. A.; Oelkers, R. J.; Frinchaboy, P. M.; Sobeck, J. S.; Román-Zúñiga, C.; Andrews, B.; Bender, C.; Carlberg, J. K.; Munn, J.; Szigetiáros, L.; Troup, N.
United States, Chile, Canada, Brazil, Spain, Hungary, Germany, Poland, Mexico
Abstract
APOGEE-2 is a high-resolution, near-infrared spectroscopic survey observing ∼3 × 105 stars across the entire sky. It is the successor to APOGEE and is part of the Sloan Digital Sky Survey IV (SDSS-IV). APOGEE-2 is expanding on APOGEE's goals of addressing critical questions of stellar astrophysics, stellar populations, and Galactic chemodynamical evolution using (1) an enhanced set of target types and (2) a second spectrograph at Las Campanas Observatory in Chile. APOGEE-2 is targeting red giant branch and red clump stars, RR Lyrae, low-mass dwarf stars, young stellar objects, and numerous other Milky Way and Local Group sources across the entire sky from both hemispheres. In this paper, we describe the APOGEE-2 observational design, target selection catalogs and algorithms, and the targeting-related documentation included in the SDSS data releases.