Extremely metal-poor stars in the local Universe reveal the properties of the first stars, which would benefit the interpretation of the recent direct observations of the high-redshift Universe by JWST. The Gaia DR3, which happened last year, has allowed the community to identify candidates of bright, extremely metal-poor stars with [Fe/H]<−3 and G<13 across all-sky for the first time. We here propose to conduct a “snap-shot” high-resolution spectroscopy for ∼ 150 of them, of which ∼ 10 stars are expected to be [Fe/H]<−3.5. After confirming their metallicity with the snap-shot, we will further conduct a higher S/N spectroscopy for 50 selected stars to trace the chemical evolution trend at [Fe/H]<−3. In particular, we will be able to study Zn and Eu abundances without being affected by detection limits thanks to the brightness of the stars and hence high S/N of the spectra; while Zn abundance constrains the impact that the first stars had on subsequent star formation, Eu provides an insight into the origin of the first heavy elements. Given that the targets are selected from catalogs that have been publicly released recently, we propose to complete both the snap-shot and high-S/N spectroscopy in the S23B semester to produce impactful results.
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