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We present the metallicities and carbon abundances of four newly discovered metal-poor stars with $ -2.2 <$ [Fe/H] $< -1.6$ in the Sagittarius dwarf spheroidal galaxy. These stars were selected as metal-poor member candidates using a combination of public photometry from the SkyMapper Southern Sky Survey and proper motion data from the second data release from the Gaia mission. The SkyMapper filters include a metallicity-sensitive narrow-band $v$ filter centered on the Ca II K line, which we use to identify metal-poor candidates. In tandem, we use proper motion data to remove metal-poor stars that are not velocity members of the Sagittarius dwarf spheroidal galaxy. We find that these two datasets allow for efficient identification of metal-poor members of the Sagittarius dwarf galaxy to follow-up with further spectroscopic study. Two of the stars we present have [Fe/H] $< -2.0$, which adds to the few other such stars currently identified in the Sagittarius dwarf galaxy that are likely not associated with the globular cluster M54, which resides in the nucleus of the system. Our results confirm that there exists a very metal-poor stellar population in the Sagittarius dwarf galaxy. We find that none of our stars can be classified as carbon-enhanced metal-poor stars. Efficiently identifying members of this population will be helpful to further our understanding of the early chemical evolution of the system.
We present spectroscopic observations from the {it Spitzer Space Telescope} of six carbon-rich AGB stars in the Sagittarius Dwarf Spheroidal Galaxy (Sgr dSph) and two foreground Galactic carbon stars. The band strengths of the observed C$_2$H$_2$ and
We report the discovery of two Mira variable stars (Miras) toward the Sextans dwarf spheroidal (dSph) galaxy. We performed optical long-term monitoring observations for two red stars in the Sextans dSph. The light curves of both stars in the $I_{rm c
The study of the chemical abundances of metal-poor stars in dwarf galaxies provides a venue to constrain paradigms of chemical enrichment and galaxy formation. Here we present metallicity and carbon abundance measurements of 100 stars in Sculptor fro
Sagittarius (Sgr) is a massive disrupted dwarf spheroidal galaxy in the Milky Way halo that has undergone several stripping events. Previous chemical studies were restricted mainly to a few, metal- rich ([Fe/H]~ -1) stars that suggested a top-light i
Although true metal-free Population III stars have so-far escaped discovery, their nature, and that of their supernovae, is revealed in the chemical products left behind in the next generations of stars. Here we report the detection of an ultra-metal