Related papers: A method for identifying metal-poor stars with Gai…

This work presents the medium-resolution ($R \sim 1,500$) spectroscopic follow-up of 522 low-metallicity star candidates from the Southern Photometric Local Universe Survey (S-PLUS). The objects were selected from narrow-band photometry,…

Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ${\sim} 8,000$ metal-poor stars ([Fe/H] $\leq -0.8$) compiled from the RAdial Velocity Experiment (RAVE) Data Release 6. Selected as…

We report on two major surveys for metal-poor stars in the galactic halo, the HK survey, and the Hamburg/ESO survey, which have been undertaken in order to provide targets for high-resolution spectroscopy with the Subaru HDS and other large…

Aims. Gaia DR3 GSP-Phot and GSP-Spec parameters of known K- and M-type stars with luminosity class I are examined and compared with parameters collected from the literature, to assess their accuracy and their potential for stellar…

Context: Studies of extremely metal-poor stars indicate that chemical abundance ratios [X/Fe] have an rms scatter as low as 0.05 dex (12 \%). It remains unclear whether this reflects observational uncertainties or intrinsic astrophysical…

Studies of the early chemical evolution of some larger dwarf galaxies ( $>10^7$ solar masses) are limited by the small number of stars known at low metallicities in these systems. Here we present metallicities and carbon abundances for…

We present a homogeneous chemical abundance analysis of 16 elements in 190 metal-poor Galactic halo stars (38 program and 152 literature objects). The sample includes 171 stars with [Fe/H] < -2.5, of which 86 are extremely metal poor,…

In this work, we present high-resolution spectroscopic observations for six metal-poor stars with [Fe/H]<-3 (including one with [Fe/H]<-4), selected using narrow-band Ca II HK photometry from the DECam MAGIC Survey. The spectroscopic data…

Infrared OH lines at 1.55 - 1.56 um in the H-band were obtained with the Phoenix high-resolution spectrograph at the 2.1m telescope of the Kitt Peak National Observatory for a sample of 14 metal-poor stars. Detailed analyses of the sample…

The Pristine-\textit{Gaia} synthetic catalogue provides reliable photometric metallicities for $\sim$30 million FGK stars using the Pristine survey model and Gaia XP spectra. We perform the first low-to-medium-resolution spectroscopic…

An accurate and precise Kepler Stellar Properties Catalog is essential for the interpretation of the Kepler exoplanet survey results. Previous Kepler Stellar Properties Catalogs have focused on reporting the best-available parameters for…

The most metal-poor stars in the Milky Way witnessed the early phases of formation of the Galaxy, and have chemical compositions that are close to the pristine mixture from Big Bang nucleosynthesis, polluted by one or few supernovae. Only…

We present a method for the determination of [alpha/Fe] ratios from low-resolution (R = 2000) SDSS/SEGUE stellar spectra. By means of a star-by-star comparison with degraded spectra from the ELODIE spectral library and with a set of…

To calibrate automatic pipelines that determine atmospheric parameters of stars, one needs a sample of stars -- ``benchmark stars'' -- with well defined parameters to be used as a reference We provide a detailed documentation of the…

The discovery of the massive black hole (BH) system Gaia BH3 in pre-release Gaia DR4 data suggests that wide BH binaries with luminous companions may be significantly overrepresented at low metallicities. Motivated by this finding, we have…

The origin of the Galactic halo is one of the fundamental topics linking the study of galaxy formation and evolution to cosmology. We aim at deriving precise and accurate stellar parameters, Mg abundances, and ages for a sample of…

We study the age and metallicity distribution function (MDF) of metal-poor stars in the Milky Way halo as a function of galactocentric radius by combining N-body simulations and semi-analytical methods. We find that the oldest stars…

We present initial results measuring the companion fraction of metal-poor stars ([Fe/H]$<-$2.0). We are employing the Lick Observatory planet-finding system to make high-precision Doppler observations of these objects. The binary fraction…

High-resolution, high-signal-to-noise (<S/N> = 85) spectra have been obtained for five stars -- CD-24:17504, CD-38:245, CS 22172-002, CS 22885-096, and CS 22949-037 -- having [Fe/H] < -3.5 according to previous lower S/N material. LTE…

RR Lyrae stars in the bulge have been reported to be associated with the spheroidal, relatively metal-poor component. They offer a way to trace this component with precise distances. While a few studies of RR Lyrae spectra with medium/high…