Journal•ISSN: 0365-0138
Astronomy & Astrophysics Supplement Series
EDP Sciences
About: Astronomy & Astrophysics Supplement Series is an academic journal. The journal publishes majorly in the area(s): Stars & Galaxy. Over the lifetime, 3249 publications have been published receiving 102761 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: The SExtractor ( Source Extractor) as mentioned in this paper is an automated software that optimally detects, deblends, measures and classifies sources from astronomical images, which is particularly suited to the analysis of large extragalactic surveys.
Abstract: We present the automated techniques we have developed for new software that optimally detects, deblends, measures and classifies sources from astronomical images: SExtractor ( Source Extractor ). We show that a very reliable star/galaxy separation can be achieved on most images using a neural network trained with simulated images. Salient features of SExtractor include its ability to work on very large images, with minimal human intervention, and to deal with a wide variety of object shapes and magnitudes. It is therefore particularly suited to the analysis of large extragalactic surveys.
10,983 citations
TL;DR: In this article, a large grid of stellar evolution-ary tracks, which are suitable to model star clusters and galaxies by means of population synthesis, is presented for the initial chemical compositions.
Abstract: We present a large grid of stellar evolution- ary tracks, which are suitable to modelling star clusters and galaxies by means of population synthesis. The tracks are presented for the initial chemical compositions (Z = 0:0004;Y =0 :23), (Z =0 :001;Y =0 :23), (Z =0 :004;Y = 0:24), (Z =0 :008;Y =0 :25), (Z =0 :019;Y =0 :273) (solar composition), and (Z =0 :03;Y =0 :30). They are com- puted with updated opacities and equation of state, and a moderate amount of convective overshoot. The range of initial masses goes from 0:15 M to 7 M ,a nd the evo- lutionary phases extend from the zero age main sequence (ZAMS) till either the thermally pulsing AGB regime or carbon ignition. We also present an additional set of mod- els with solar composition, computed using the classical Schwarzschild criterion for convective boundaries. From all these tracks, we derive the theoretical isochrones in the Johnson-Cousins UBVRIJHK broad-band photometric system.
2,609 citations
TL;DR: The CHIANTI database as mentioned in this paper is a set of atomic data and transition probabilities necessary to calculate the emission line spectrum of astrophysical plasmas, including atomic energy levels, atomic radiative data such as wavelengths, weighted oscillator strengths and A values, and electron collisional excitation rates.
Abstract: CHIANTI consists of a critically evaluated set of atomic data and transition probabilities necessary to calculate the emission line spectrum of astrophysical plasmas. The data consist of atomic energy levels, atomic radiative data such as wavelengths, weighted oscillator strengths and A values, and electron collisional excitation rates. A set of programs that use these data to calculate the spectrum in a desired wavelength range as a function of temperature and density is also provided. A suite of programs has been developed to carry out plasma diagnostics of astrophysical plasmas. The state-of-the-art contents of the CHIANTI database will be described and some of the most important results obtained from the use of the CHIANTI database will be reviewed.
2,116 citations
TL;DR: SIMBAD as discussed by the authors is the astronomical data base produced and maintained by the Centre de Donnees astronomiques de Strasbourg (CDS) at the Observatoire of Strasbourg, France.
Abstract: SIMBAD is the astronomical data base produced and maintained by the Centre de Donnees astronomiques de Strasbourg (CDS), at the Observatoire de Strasbourg, France.
1,684 citations
TL;DR: The updated version of the “Vienna Atomic Line Data Base” (VALD) is described which represents a considerable improvement over the first installation from 1994 and the future roadmap of VALD developments is discussed, including the incorporation of molecular transitions and integration with external data bases.
Abstract: We describe the updated version of the “Vienna Atomic Line Data Base” (VALD, Piskunov et al. 1995) which represents a considerable improvement over the first installation from 1994. The original line lists have been complemented with critically evaluated data obtained from experimental measurements and theoretical calculations which are necessary for computing state-of-the-art line opacities in stellar atmospheres, as well as for synthesizing spectra for high precision analyses. In this paper, we present new and improved data sets for neutral species and ions of Si, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Ru, Xe, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Re, Pt, Au, Hg, and Pb. For some species data are available in VALD for the first time. We explain our choice of quality rankings by reviewing the literature for the new data and by comparison with source lists included into VALD. For some cases, we produced new line data by weighted averaging of data from different sources with individual error estimates in order to increase the reliability of VALD line lists. Software modifications allow remote users of VALD to specify individual extraction parameters as an alternative to the default settings of the VALD team and to have direct control over the quality ranking of line data. A World–Wide–Web interface is described which provides easy access to all new features. To simplify proper crediting of all authors of atomic data, VALD now includes a compilation of all publications used in each type of reply. Finally, we briefly discuss the future roadmap of VALD developments, including the incorporation of molecular transitions and integration with external data bases.
1,641 citations