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ABUNDANCE RATIOS AND GALACTIC CHEMICAL EVOLUTION
Annual Review of Astronomy and Astrophysics, 1997▪ Abstract The metallicity of stars in the Galaxy ranges from [Fe/H] = −4 to +0.5 dex, and the solar iron abundance is ε(Fe) = 7.51 ± 0.01 dex. The average values of [Fe/H] in the solar neighborhood, the halo, and Galactic bulge are −0.2, −1.6, and −0.2 dex respectively.
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Galactic abundance gradients from Cepheids
2013International ...
Lemasle, B. +13 more
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Galactic H II Region Abundances
1999A review of the chemical abundances of Galactic H II regions is presented. The C and O abundances derived from recombination lines are higher than those derived from forbidden lines; arguments in favor of the recombination abundances are given. The Galactic abundance gradients are discussed.
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Element Abundances and Galactic Chemical Evolution
2001Recent developments in the study of element abundances and their impact on our understanding of the evolution of stars and the chemical evolution of the Galaxy are described. In particular, problems that may benefit, or benefit from, work on binary stellar populations are highlighted.
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Abundance Ratios in the Galactic Bulge
2006We present abundance results from our Keck/HIRES observations of giants in the Galactic Bulge. We confirm that the metallicity distribution of giants in the lowreddening bulge field Baade’s Window can be well-fit by a closed-box enrichment model. We also confirm previous observations that find enhanced [Mg/Fe], [Si/Fe] and [Ca/Fe] for all bulge giants,
J.P. Fulbright +2 more
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Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources
Nature, 2021Zhen Cao, Felix Aharonian, Yiwei Bao
exaly
“Liners” and Abundances in Galactic Nuclei
1984[NII] λλ 6548, 6584 increase in strength relative to Hα in HII regions as the overall abundance of heavy elements is increased, but in some galactic nuclei λ6584 is still stronger than Hα, which never happens in conventional HII regions ionised by hot stars.
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All-sky dynamical response of the Galactic halo to the Large Magellanic Cloud
Nature, 2021Charlie Conroy +2 more
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Abundance Gradients Along the Galactic Disk
2000The observtional evidence for abundance gradients along the Galactic disk is reviewed. Results from various methods and objects used to probe the metallicity of the disk are discussed and the quantatative results are compared.
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