相关论文: Photometric Abundances for G-Dwarfs: A Cautionary …

We examine the correlation between stellar metallicity and short period planets. It appears that approximately 1% of dwarf stars in the solar neighborhood harbor short-period planets characterized by near-circular orbits and orbital periods…

We present stellar parameters and metallicities for 29 planet-host stars, as well as for a large volume-limited sample of 53 stars not known to be orbited by any planetary-mass companion. These stars add to the results presented in our…

We report detailed analysis of high-resolution spectra of nine high velocity metal-rich dwarfs in the solar neighborhood. The stars are super metal-rich and 5 of them have [Fe/H]>=+0.4, making them the most metal-rich stars currently known.…

With the goal of confirming the metallicity "excess" present in stars with planetary-mass companions, we present in this paper a high-precision spectroscopic study of a sample of dwarfs included in the CORALIE extrasolar planet survey. The…

Large numbers of low-to-medium resolution spectra of M-type dwarf stars from both the local Galactic disk and halo are available from various surveys. In order to fully exploit these data, we develop a template-fit method using a set of…

Open clusters are a useful tool when investigating several topics connected with stellar evolution; for example the age or distance can be more accurately determined than for field stars. However, one important parameter, the metallicity,…

ABRIDGED: METHODS: We have conducted a high-resolution spectroscopic study of 714 F and G dwarf and subgiant stars in the Solar neighbourhood. The star sample has been kinematically selected to trace the Galactic thin and thick disks to…

We have derived elemental abundances of O, Na, Mg, Al, Si, Ca, Ti, Cr, Mn, Fe, Co, Ni for 47 G and K dwarf, with [Me/H]>0.1 dex. The selection of stars was based on their kinematics as well as on their uvby-photometry. One sample of stars…

Assuming that in the atmospheres of low-mass, metal-poor red giant stars, 1-D models based on LTE accurately predict the abundance of iron from Fe II, we derive a globular cluster metallicity scale based on the equivalent widths of Fe II…

We present a recalibration of the luminosity-metallicity relation for gas-rich, star-forming dwarfs to magnitudes as faint as M$_R$ ~ -13. We use the Dopita et al. (2013) metallicity calibrations to calibrate the relation for all of the…

We study dwarf galaxies in the Centaurus A group to investigate their metallicity and possible environmental effects. The Centaurus A group (at ~4 Mpc from the Milky Way) contains about 50 known dwarf companions of different morphologies…

The metal content of planet hosting stars is an important ingredient which may affect the formation and evolution of planetary systems. Accurate stellar abundances require the determinations of reliable physical parameters, namely the…

Multiple populations are ubiquitous in the old massive globular clusters (GCs) of the Milky Way. It is still unclear how they arose during the formation of a GC. The topic of iron and metallicity variations has recently attracted attention…

The study of chemical abundances in stars with planets is an important ingredient for the models of formation and evolution of planetary systems. In order to determine accurate abundances, it is crucial to have a reliable set of atmospheric…

We present magnesium abundances derived from high resolution spectra using several Mg I and two high excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic…

We derive stellar ages, from evolutionary tracks, and metallicities, from Stromgren photometry, for a sample of 5828 dwarf and sub-dwarf stars from the Hipparcos Catalogue. This stellar disk sample is used to investigate the age-metallicity…

We present a new calibration of the seven-color Vilnius system in terms of [Fe/H], applicable to F-M stars in the metallicity range -2.8<[Fe/H]<+0.5. We employ a purely empirical approach, based on ~1000 calibrating stars with…

The cosmic origin of fluorine is still not well constrained. Several nucleosynthetic channels at different phases of stellar evolution have been suggested, but these must be constrained by observations. For this, the fluorine abundance…

We investigated almost 500 stars distributed among 193 binary or multiple systems made of late-F, G-, or early-K primaries and late-K or M dwarf companion candidates. For all of them, we compiled or measured coordinates, J-band magnitudes,…

We focus on the resolved stellar populations of one early- and four transition-type dwarf galaxies in the Sculptor group, with the aim to examine the potential presence of population gradients and place constraints on their mean…