We present a chemical and dynamical analysis of the leading arm (LA) and trailing arm (TA) of the Sagittarius (Sgr) stream, as well as for the Sgr dwarf galaxy core (SC), using red giant branch, main-sequence, and RR Lyrae stars from large spectroscopic survey data. The different chemical properties among the LA, TA, and SC generally agree with recent studies and can be understood by a radial metallicity gradient established in the progenitor of the Sgr dwarf, followed by preferential stellar stripping from the outer part of the Sgr progenitor. One striking finding is a relatively larger fraction of low-eccentricity stars (
- Award ID(s):
- 1927130
- PAR ID:
- 10543450
- Publisher / Repository:
- APJL
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 954
- Issue:
- 2
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L43
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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