Results 21 to 30 of about 226,407 (198)
Chemical Abundances in Galactic Bulge Pn [PDF]
Symposium - International Astronomical Union, 1993 We present abundance determinations, in particular of carbon, and C/O ratios, for 11 Galactic bulge planetary nebulae (PN) based on our low resolution UV data from IUE observations and optical spectrophotometry from the Anglo-Australian Telescope. We compare the observed abundances with those predicted by dredge-up theory for the high metallicity ...
N. A. Walton +2 more
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Chemical Abundances in Symbiotic Stars [PDF]
The Astrophysical Journal, 2008 We have carried out a study of the chemical abundances of $^1$H, $^4$He, $^{12}$C, $^{13}$C, $^{14}$N, $^{15}$N, $^{16}$O, $^{17}$O, $^{20}$Ne and $^{22}$Ne in symbiotic stars (SSs) by means of a population synthesis code. We find that the ratios of the number of O-rich SSs to that of C-rich SSs in our simulations are between 3.4 and 24.1, depending on
Lu, Guoliang +3 more
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Chemical abundances in Seyfert galaxies VI. Empirical abundance calibration
, 2021 9 pages, 7 figures, accepted for publication in ...
Dors, L, O.
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Chemical Abundances as Population Tracers [PDF]
, 2013 Chapter to appear in textbook "Planets, Stars & Stellar Systems", Vol. 5, Ed. G. Gilmore, Springer-Verlag.
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Li-rich Giants Identified from LAMOST DR8 Low-resolution Survey
The Astronomical Journal, 2023 A small fraction of giants possess photospheric lithium (Li) abundance higher than the value predicted by the standard stellar evolution models, and the detailed mechanisms of Li enhancement are complicated and lack a definite conclusion.
Beichen Cai +5 more
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Chemical Abundances and Hierarchical Clustering [PDF]
Symposium - International Astronomical Union, 2004 In this contribution we study the chemical enrichment of the interstellar medium and stellar population of the building blocks of current typical galaxies in the field, in cosmological hydrodynamics simulations. The simulations include detailed modeling of chemical enrichment by SNIa and SNII In our simulations the missing metal problem is caused by ...
P. B. Tissera, D.G. Lambas
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Search for Extremely Metal-poor Stars with Gemini-N/Graces. I. Chemical-abundance Analysis
The Astrophysical Journal, 2023 We present stellar parameters and abundances of 13 elements for 18 very metal-poor (VMP; [Fe/H] < –2.0) stars, selected as extremely metal-poor (EMP; [Fe/H] < –3.0) candidates from the Sloan Digital Sky Survey and Large sky Area Multi-Object Fiber ...
Miji Jeong +7 more
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, 2012 High-resolution H-band spectra of five bright field K, M, and MS giants, obtained from the archives of the Kitt Peak National Observatory (KPNO) Fourier Transform Spectrometer (FTS), are analyzed to determine chemical abundances of 16 elements.
Bizyaev, Dmitry +10 more
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Recent Development of the Atomic Line List
Galaxies, 2018 The Atomic Line List is an online database of wavelengths and transition probabilities of atomic lines. It is primarily set up as a tool to help identify unknown spectral features.
Peter A. M. van Hoof
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Radial molecular abundances and gas cooling in starless cores
, 2012 Aims: We aim to simulate radial profiles of molecular abundances and the gas temperature in cold and heavily shielded starless cores by combining chemical and radiative transfer models.
Aikawa +46 more
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