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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 from medium-resolution (R ~ 2000) spectra taken with the Magellan/Michigan Fiber System mounted on the Magellan-Clay 6.5m telescope at Las Campanas Observatory. We identify 24 extremely metal-poor star candidates ([Fe/H] < -3.0) and 21 carbon-enhanced metal-poor (CEMP) star candidates. Eight carbon-enhanced stars are classified with at least 2$sigma$ confidence and five are confirmed as such with follow-up R~6000 observations using the Magellan Echellette Spectrograph on the Magellan-Baade 6.5m telescope. We measure a CEMP fraction of 36% for stars below [Fe/H] = -3.0, indicating that the prevalence of carbon-enhanced stars in Sculptor is similar to that of the halo (~43%) after excluding likely CEMP-s and CEMP-r/s stars from our sample. However, we do not detect that any CEMP stars are strongly enhanced in carbon (e.g., [C/Fe] > 1.0). The existence of a large number of CEMP stars both in the halo and in Sculptor suggests that some halo CEMP stars may have originated from accreted early analogs of dwarf galaxies.
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 p
The carbon-enhanced metal-poor (CEMP) stars constitute approximately one fifth of the metal-poor ([Fe/H] ~< -2) population but their origin is not well understood. The most widely accepted formation scenario, invokes mass-transfer of carbon-rich mate
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 $I_{rm c
Although true metal-free Population III stars have so-far escaped discovery, their nature, and that of their supernovae, is revealed in the chemical products left behind in the next generations of stars. Here we report the detection of an ultra-metal
We present spectroscopic observations from the {it Spitzer Space Telescope} of six carbon-rich AGB stars in the Sagittarius Dwarf Spheroidal Galaxy (Sgr dSph) and two foreground Galactic carbon stars. The band strengths of the observed C$_2$H$_2$ and