We present a chemodynamical study of the Grus I ultra-faint dwarf galaxy (UFD) from medium-resolution (
This content will become publicly available on June 1, 2024
In this paper, we present a chemical and kinematic analysis of two ultrafaint dwarf galaxies (UFDs), Aquarius II (Aqu II) and Boötes II (Boo II), using Magellan/IMACS spectroscopy. We present the largest sample of member stars for Boo II (12), and the largest sample of red giant branch members with metallicity measurements for Aqu II (eight). In both UFDs, over 80% of targets selected based on Gaia proper motions turned out to be spectroscopic members. In order to maximize the accuracy of stellar kinematic measurements, we remove the identified binary stars and RR Lyrae variables. For Aqu II, we measure a systemic velocity of −65.3 ± 1.8 km s−1and a metallicity of [Fe/H] =
- Award ID(s):
- 1813881
- NSF-PAR ID:
- 10475452
- Publisher / Repository:
- American Astronomical Society Journals
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 950
- Issue:
- 2
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 167
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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