相关论文: Spectral models for solar-scaled and alpha-enhance…

The primary objective of this study is to accurately determine the abundances of Cu, Sr, Y, Zr, Ba, La, and Ce in selected solar-type stars. This will allow us to establish observational abundance-metallicity and abundance-age relations and…

We use empirical star formation histories (SFHs), measured from HST-based resolved star color-magnitude diagrams, as input into population synthesis codes to model the broadband spectral energy distributions (SEDs) of ~50 nearby dwarf…

We present element-to-element abundance ratios measured from high dispersion spectra for 150 field subdwarfs and early subgiants with accurate Hipparcos parallaxes (errors <20%). For 50 stars new spectra were obtained with the UVES on…

Sulfur is a volatile chemical element that plays an important role in tracing the chemical evolution of galaxies. However, its nucleosynthesis origin and abundance variations are still unclear. The goal of the present article is to…

We report results from the high resolution spectral analysis of the 107 metal rich (mostly [Fe/H]$\ge$7.67 dex) target stars from the Calan-Hertfordshire Extrasolar Planet Search program observed with HARPS. Using our procedure of finding…

Spectral evolution models are a widely used tool for determining the stellar content of galaxies. I provide a review of the latest developments in stellar atmosphere and evolution models, with an emphasis on massive stars. In contrast to…

We present robust statistical estimates of the accuracy of early-type galaxy stellar masses derived from spectral energy distribution (SED) fitting as functions of various empirical and theoretical assumptions. Using large samples…

We present preliminary results for estimation of barium ([Ba/Fe]) and strontium ([Sr/Fe]) abundances ratios using medium-resolution spectra (1-2 {\AA}). We established a calibration between the abundance ratios and line indices for Ba and…

We present a joint analysis of the four most prominent sodium-sensitive features (NaD, NaI8190, NaI1.14, and NaI2.21), in the optical and Near-Infrared spectral range, of two nearby, massive (sigma~300km/s), early-type galaxies (named XSG1…

The evolution and explosion of metal-free stars with masses 10--100 solar masses are followed, and their nucleosynthetic yields, light curves, and remnant masses determined. When the supernova yields are integrated over a Salpeter initial…

We have performed accurate iron abundance measurements for 44 red giants (RGs) in the Carina dwarf spheroidal (dSph) galaxy. We used archival, high-resolution spectra (R~38,000) collected with UVES at ESO/VLT either in slit mode (5) or in…

Abundances for Fe, O, and the alpha-elements (Mg, Si, Ca, and Ti) have been derived from high resolution spectra of a sample of about one hundred dwarfs with high precision parallaxes measured by HIPPARCOS. The stars have metal abundances…

The evolution of galaxies is imprinted in their stellar populations. Several stellar population properties in massive early-type galaxies have been shown to correlate with intrinsic galaxy properties like the galaxy's central velocity…

We present new analytic solutions for one-zone (fully mixed) chemical evolution models and explore their implications. In contrast to existing analytic models, we incorporate a realistic delay time distribution for Type Ia supernovae (SNIa)…

Theories of thick disk formation can be differentiated by measurements of stellar elemental abundances. We have undertaken a study of metal-poor stars selected from the RAVE spectroscopic survey of bright stars to establish whether or not…

Exploring the Galactic chemical evolution and enrichment scenarios with open clusters allows us to understand the history of the Milky Way disk. High-resolution spectra of OCs are a crucial tool, as they provide precise chemical…

The study of galaxy evolution hinges on our ability to interpret multi-wavelength galaxy observations in terms of their physical properties. To do this, we rely on spectral energy distribution (SED) models which allow us to infer physical…

Metal-poor M subdwarfs are among the oldest stellar populations and carry valuable information about the chemical enrichment history of the Milky Way. The measurements of chemical abundances of these stars therefore provide essential…

Deriving accurate carbon abundance estimates for a wide variety of stars is still complex due to the difficulties in properly measuring it from atomic and molecular lines. The aim of this paper is to analyse the carbon abundance…

We measure abundances of 12 elements (Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni) in a sample of 86 metal-poor ($-2 \lesssim \text{[Fe/H]} \lesssim -1$) subgiant stars in the solar neighborhood. Abundances are derived from…