Preliminary Target Selection for the DESI Milky Way Survey (MWS)

Carlos Allende Prieto; Andrew P. Cooper; Arjun Dey; Boris T. Gänsicke; Sergey E. Koposov; Ting Li; Christopher Manser; David L. Nidever; Constance Rockosi; Mei-Yu Wang; David S. Aguado; Robert Blum; David Brooks; Daniel J. Eisenstein; Yutong Duan; Sarah Eftekharzadeh; Enrique Gaztañaga; Robert Kehoe; Martin Landriau; Chien-Hsiu Lee; Michael E. Levi; Aaron M. Meisner; Adam D. Myers; Joan Najita; Knut Olsen; Nathalie Palanque-Delabrouille; Claire Poppett; Francisco Prada; David J. Schlegel; Michael Schubnell; Gregory Tarlé; Monica Valluri; Risa H. Wechsler; Christophe Yèche

doi:10.3847/2515-5172/abc1dc

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arXiv · 2010.11284

Preliminary Target Selection for the DESI Milky Way Survey (MWS)

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Abstract

The DESI Milky Way Survey (MWS) will observe $\ge$8 million stars between $16 < r < 19$ mag, supplemented by observations of brighter targets under poor observing conditions. The survey will permit an accurate determination of stellar kinematics and population gradients; characterize diffuse substructure in the thick disk and stellar halo; enable the discovery of extremely metal-poor stars and other rare stellar types; and improve constraints on the Galaxy's 3D dark matter distribution from halo star kinematics. MWS will also enable a detailed characterization of the stellar populations within 100 pc of the Sun, including a complete census of white dwarfs. The target catalog from the preliminary selection described here is public.

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Carlos Allende Prieto, Andrew P. Cooper, Arjun Dey, Boris T. Gänsicke, Sergey E. Koposov, Ting Li, Christopher Manser, David L. Nidever, Constance Rockosi, Mei-Yu Wang, David S. Aguado, Robert Blum, David Brooks, Daniel J. Eisenstein, Yutong Duan, Sarah Eftekharzadeh, Enrique Gaztañaga, Robert Kehoe, Martin Landriau, Chien-Hsiu Lee, Michael E. Levi, Aaron M. Meisner, Adam D. Myers, Joan Najita, Knut Olsen, Nathalie Palanque-Delabrouille, Claire Poppett, Francisco Prada, David J. Schlegel, Michael Schubnell, Gregory Tarlé, Monica Valluri, Risa H. Wechsler, Christophe Yèche. 2020-10-21. Preliminary Target Selection for the DESI Milky Way Survey (MWS). https://doi.org/10.3847/2515-5172/abc1dc

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