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Abstract The Sloan Digital Sky Survey-V (SDSS-V) Magellanic Genesis Survey is a spectroscopic program designed to map the kinematic and chemical structure of the Magellanic Clouds (MCs) using APOGEE and BOSS spectroscopy. This overview describes the survey’s design, target selection, and science goals and highlights some first results using these data. In the inner regions of the Large and Small Magellanic Clouds (LMC and SMC), the survey obtained high-resolution near-infrared APOGEE spectra (S/N ≈ 45) of ∼14,000 bright, oxygen-rich asymptotic giant branch (AGB-O) stars. These data provide contiguous spatial coverage of the MCs’ main bodies, enabling detailed chemodynamical studies. To explore extended structures, the survey includes BOSS optical spectroscopy of fainter red giant stars selected with Gaia DR3 data, reachingG ≈ 17.5. Many of these targets extend to the outer regions of the MCs, which are known to span ∼20° (LMC) and ∼12° (SMC) and contain diffuse substructures of unclear origin. BOSS data in the inner regions also complement APOGEE by providing elements inaccessible in the near-infrared and enabling cross-calibration between instruments. The survey further includes APOGEE and BOSS observations of ∼300 evolved massive stars and a small sample of symbiotic binaries previously observed by APOGEE-1 and APOGEE-2, enhancing our understanding of massive stellar evolution and complementing the SDSS-V main-sequence massive star program.
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This content will become publicly available on March 30, 2027
Mapping the Distant and Metal-poor Milky Way with SDSS-V
Abstract The fifth-generation Sloan Digital Sky Survey (SDSS-V) is conducting the first all-sky low-resolution spectroscopic survey of the Milky Way’s (MW) stellar halo. We describe the stellar parameter pipeline for the SDSS-V halo survey, which simultaneously models spectra, broadband photometry, and parallaxes to derive stellar parameters, metallicities, alpha abundances, and distances. The resulting Baryon Oscillation Spectroscopic Survey (BOSS)-MINESweepercatalog is validated across a wide range of stellar parameters and metallicities using star clusters and a comparison to high-resolution spectroscopic surveys. We demonstrate several scientific capabilities of this dataset: identifying the most chemically peculiar stars in our Galaxy, discovering and mapping distant halo substructures, and measuring the all-sky dynamics of the MW on the largest scales. The BOSS-MINESweepercatalog for SDSS DR19 is publicly available and will be updated for future data releases.
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- Award ID(s):
- 2510795
- PAR ID:
- 10699193
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 1000
- Issue:
- 2
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 283
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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