Preliminary Target Selection for the DESI Bright Galaxy Survey (BGS)

Omar Ruiz-Macias; Pauline Zarrouk; Shaun Cole; Peder Norberg; Carlton Baugh; David Brooks; Arjun Dey; Yutong Duan; Sarah Eftekharzadeh; Daniel J. Eisenstein; Jaime E. Forero-Romero; Enrique Gaztañaga; ChangHoon Hahn; Robert Kehoe; Martin Landriau; Dustin Lang; Michael E. Levi; John Lucey; Aaron M. Meisner; John Moustakas; Adam D. Myers; Nathalie Palanque-Delabrouille; Claire Poppett; Francisco Prada; Anand Raichoor; David J. Schlegel; Michael Schubnell; Gregory Tarlé; David H. Weinberg; M. J. Wilson; Christophe Yèche

doi:10.3847/2515-5172/abc25a

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arXiv · 2010.11283

Preliminary Target Selection for the DESI Bright Galaxy Survey (BGS)

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Abstract

The Dark Energy Spectroscopic Instrument (DESI) will execute a nearly magnitude-limited survey of low redshift galaxies ($0.05 \leq z \leq 0.4$, median $z \approx 0.2$). Clustering analyses of this Bright Galaxy Survey (BGS) will yield the most precise measurements to date of baryon acoustic oscillations and redshift-space distortions at low redshift. DESI BGS will comprise two target classes: (i) BRIGHT ($r<19.5$~mag), and (ii) FAINT ($19.5<r<20$~mag). Here we present a summary of the star-galaxy separation, and different photometric and geometrical masks, used in BGS to reduce the number of spurious targets. The selection results in a total density of $\sim 800$ objects/deg$^2$ for the BRIGHT and $\sim 600$ objects/deg$^2$ for the FAINT selections.A full characterization of the BGS selection can be found in Ruiz-Macias et al. (2020).

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Omar Ruiz-Macias, Pauline Zarrouk, Shaun Cole, Peder Norberg, Carlton Baugh, David Brooks, Arjun Dey, Yutong Duan, Sarah Eftekharzadeh, Daniel J. Eisenstein, Jaime E. Forero-Romero, Enrique Gaztañaga, ChangHoon Hahn, Robert Kehoe, Martin Landriau, Dustin Lang, Michael E. Levi, John Lucey, Aaron M. Meisner, John Moustakas, Adam D. Myers, Nathalie Palanque-Delabrouille, Claire Poppett, Francisco Prada, Anand Raichoor, David J. Schlegel, Michael Schubnell, Gregory Tarlé, David H. Weinberg, M. J. Wilson, Christophe Yèche. 2020-10-21. Preliminary Target Selection for the DESI Bright Galaxy Survey (BGS). https://doi.org/10.3847/2515-5172%2Fabc25a

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