WAN , Zhen

We present a comprehensive metallicity analysis of the Sagittarius dwarf spheroidal galaxy (Sgr dSph) using Pristine CaHK photometry. We base our member selection on Gaia EDR3 astrometry applying a magnitude limit at G0 = 17.3, and our population study on the metallicity-sensitive photometry from the Pristine Inner Galaxy Survey (PIGS). Working...

The most metal-deficient stars hold important clues about the early buildup and chemical evolution of the Milky Way, and carbon-enhanced metal-poor (CEMP) stars are of special interest. However, little is known about CEMP stars in the Galactic bulge. In this paper, we use the large spectroscopic sample of metal-poor stars from the Pristine...

Metal-poor stars are important tools for tracing the early history of the Milky Way, and for learning about the first generations of stars. Simulations suggest that the oldest metal-poor stars are to be found in the inner Galaxy. Typical bulge surveys, however, lack low metallicity (⁠[Fe/H]<−1.0⁠) stars because the inner Galaxy is predominantly...