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Analysis of chemical abundances in planetary nebulae with [WC] central stars II. Chemical abundances and the abundance discrepancy factor
(EDP Sciences, 2013)
Aims. We present the abundance analysis of 12 planetary nebulae ionized by [WC]-type stars and weak-emission-line stars (wels)
obtained from high-resolution spectrophotometric data. Our main aims are to determine the ...
Chemical composition of a sample of bright solar-metallicity stars
(WILEY-V C H VERLAG GMBH, 2015)
We present a detailed analysis of seven young stars observed with the spectrograph SOPHIE at the Observatoire de Haute-Provence for which the chemical composition was incomplete or absent in the literature. For five stars, ...
Propiedades físicas de estrellas con exoplanetas y anillos circunestelares /
(2008-03)
Estudiamos diferentes aspectos de estrellas con exoplanetas (EH) y de estrellas de tipo Vega. Detectamos excesos IR en 20% de las estrellas EH, el cual se atribuye a la presencia de polvo circunestelar.
The first chemical abundance analysis of K giants in the inner Galactic disc
(2010)
Aims. The elemental abundance structure of the Galactic disc has been extensively studied in the solar neighbourhood using long-lived stars such as F and G dwarfs or K and M giants. These are stars whose atmospheres preserve ...
Abundance ratios of red giants in low-mass ultra-faint dwarf spheroidal galaxies
(EDP SCIENCES, 2016-04)
Context. Low-mass dwarf spheroidal galaxies are key objects for our understanding of the chemical evolution of the pristine Universe and the Local Group of galaxies. Abundance ratios in stars of these objects can be used ...
The Gaia-ESO survey: 3D NLTE abundances in the open cluster NGC 2420 suggest atomic diffusion and turbulent mixing are at the origin of chemical abundance variations
(European Southern Observatory, 2020)
Context. Atomic diffusion and mixing processes in stellar interiors influence the structure and the surface composition of stars. Some of these processes cannot yet be modelled from the first principles, and they require ...