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A grid of MARCS model atmospheres for late-type stars. I. Methods and general properties
Context. In analyses of stellar spectra and colours, and for the analysis of integrated light from galaxies, a homogeneous grid of model atmospheres of late-type stars and corresponding flux spectra
A stellar relic from the early Milky Way
This work reports the discovery of a low-mass star with an iron abundance as low as 1/200,000 of the solar value, which suggests that population III stars could still exist and that the first generation of stars also contained long-livedLow-mass objects.
The Peculiar Solar Composition and Its Possible Relation to Planet Formation
We have conducted a differential elemental abundance analysis of unprecedented accuracy (~0.01 dex) of the Sun relative to 11 solar twins from the Hipparcos catalog and 10 solar analogs from planet
The chemical composition of carbon stars. I. Carbon, nitrogen, and oxygen in 30 cool carbon stars in the Galactic disk
The chemical compositions of 30 Galactic carbon stars are determined from high-resolution infrared (1.5-2.5 ¡im) spectra and new model atmospheres. Elemental C, N, and O abundances (with respect to
We report on a detailed abundance analysis of HE 0107� 5240, a halo giant with ½Fe=HNLTE ¼� 5:3. This star was discovered in the course of follow-up medium-resolution spectroscopy of extremely
Gaia FGK benchmark stars: Effective temperatures and surface gravities
Context. In the era of large Galactic stellar surveys, carefully calibrating and validating the data sets has become an important and integral part of the data analysis. Moreover, new generations of
Abundances in metal-rich stars. Detailed abundance analysis of 47 G and K dwarf stars with [Me/H] > 0.10 dex
We have derived elemental abundances of O, Na, Mg, Al, Si, Ca, Ti, Cr, Mn, Fe, Co, Ni as well as for a number of s-elements for 47 G and K dwarf, with [Me/H]>0.1 dex. The selection of stars was based
The r-Process-enriched Low-Metallicity Giant HD?115444
New high-resolution, very high signal-to-noise spectra of ultra-metal-poor (UMP) giant stars HD 115444 and HD 122563 have been gathered with the High-Resolution Echelle Spectrometer of the McDonald
A study of circumstellar envelopes around bright carbon stars. I: Structure, kinematics, and mass-loss rate
We have performed a survey of circumstellar CO emission on a sample of bright carbon stars, which is relatively complete out to about 900 pc from the Sun. In total, 68 detections were made. All
The Hamburg/ESO R-process enhanced star survey (HERES) - III. HE 0338-3945 and the formation of the r + s stars
We have derived abundances of 33 elements and upper limits for 6 additional elements for the metal-poor (${\rm [Fe/H]} = -2.42$) turn-off star HE 0338-3945 from high-quality VLT-UVES spectra. The