Results 11 to 20 of about 5,514 (218)
Origin of Star-to-Star Abundance Inhomogeneities in Star Clusters [PDF]
Proceedings of the International Astronomical Union, 2008 AbstractThe mass reinserted by young stars of an emerging massive compact cluster shows a bimodal hydrodynamic behaviour. In the inner part of the cluster, it is thermally unstable, while in its outer parts it forms an out-blowing wind. The chemical homogeneity/inhomogeneity of low/high mass clusters demonstrates the relevance of this solution to the ...
Palouš, Jan +3 more
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Abundances in rapidly rotating a stars [PDF]
International Astronomical Union Colloquium, 1993 AbstractA study is undertaken to determine abundances in rapidly rotating main sequence A stars (v sin i = 100 − 180 km/s) in order to investigate if non-solar abundance patterns found in slow rotators (Lemke 1989, 1990) persist toward higher rotational velocities.
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Nitrogen abundances in planet-harbouring stars [PDF]
Astronomy & Astrophysics, 2004 We present a detailed spectroscopic analysis of nitrogen abundances in 91 solar-type stars, 66 with and 25 without known planetary mass companions. All comparison sample stars and 28 planet hosts were analysed by spectral synthesis of the near-UV NH band at 3360 Åobserved at high resolution with the VLT/UVES,while the near-IR NI 7468 Åwas measured in ...
Ecuvillon, A. +5 more
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Abundances of RGB stars in NGC 6752 [PDF]
Astronomy & Astrophysics, 2002 Abundances of O, Fe, Al, Mg, Na and Li determined from high-resolution and high signal{to{noise spectra of 21 red giant branch (RGB) stars in the globular cluster NGC 6752 are presented. We demonstrate that the Stromgren c1 index correlates extremely well with the measured NH, CH and CN indices and that variations in c1 are due to dierences in UV NH ...
Grundahl, F.; id_orcid 0000-0002-8736-1639 +3 more
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Atmospheric Parameters and Abundances of sdB Stars [PDF]
Astrophysics and Space Science, 2004 To appear in "Extreme Horizontal Branch Stars and Related Objects", Astrophysics and Space Science, Kluver Academic Publishers, edited by P.F.L ...
Heber, U., Edelmannn, H.
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Abundances in Wolf-Rayet Stars, LBVs and OBN Stars [PDF]
Symposium - International Astronomical Union, 1991 Current knowledge of the chemical nature of WR stars determined from UV, optical and IR spectral analyses, is reviewed. By number, the H/He ratio is low in most WN stars: 10 ≥ H/He ≥ 0.4 for WNL stars; 3.0 ≥ H/He ≥ 0.0 for WNE stars with most having near zero H-abundances.
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Abundances in extremely metal-poor stars. Comparison of the trends of abundance ratios in giants and turnoff stars [PDF]
Proceedings of the International Astronomical Union, 2005 AbstractWe show that in a sample of Extremely Metal-Poor (EMP) giants (<[Fe/H]>=−3.1) all the stars with a luminosity higher than logL/L⊙ ≈ 2.6 present the characteristics of a mixing of the surface with the H-burning layer: low abundance of carbon and high abundance of nitrogen.
Spite, M. +13 more
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Oxygen abundances in planet-harbouring stars [PDF]
Astronomy & Astrophysics, 2005 19 pages, 11 figures (low resolution), accepted for publication in A& ...
Ecuvillon, A. +5 more
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Pediatric Blood &Cancer, EarlyView.ABSTRACT Pediatric supportive care clinical trials often involve multiple clinically important outcomes, complicating trial interpretation. Hierarchical composite endpoints (HCEs) provide a framework to integrate key outcomes according to clinical importance.
Willem H. Collier +11 more
wiley +1 more source
Abundances of Extremely Metal-poor Star Candidates [PDF]
The Astronomical Journal, 2004 We present chemical abundances for 110 stars identified in objective-prism surveys as candidates to be very metal-poor. The abundances are derived from high S/N, intermediate-resolution spectra obtained with the Keck Observatory Echelle Spectrometer and Imager.
Lai, David K. +3 more
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