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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Chemical Abundances in the Leading Arm of the Magellanic Stream [PDF]
, 2018 The Leading Arm (LA) of the Magellanic Stream is a vast debris field of H i clouds connecting the Milky Way and the Magellanic Clouds. It represents an example of active gas accretion onto the Galaxy.
A. Fox +11 more
semanticscholar +1 more source
TOPoS. IV. Chemical abundances from high-resolution observations of seven extremely metal-poor stars [PDF]
, 2018 Context. Extremely metal-poor (EMP) stars provide us with indirect information on the first generations of massive stars. The TOPoS survey has been designed to increase the census of these stars and to provide a chemical inventory that is as detailed as ...
P. Bonifacio +22 more
semanticscholar +1 more source
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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Evidence for Ubiquitous Carbon Grain Destruction in Hot Protostellar Envelopes
The Astrophysical Journal Letters, 2023 Earth is deficient in carbon and nitrogen by up to ∼4 orders of magnitude compared with the Sun. Destruction of (carbon- and nitrogen-rich) refractory organics in the high-temperature planet-forming regions could explain this deficiency.
Pooneh Nazari +4 more
doaj +1 more source
JINAbase—A Database for Chemical Abundances of Metal-poor Stars [PDF]
Astrophysical Journal Supplement Series, 2017 Reconstructing the chemical evolution of the Milky Way is crucial for understanding the formation of stars, planets, and galaxies throughout cosmic time.
Abdu Abohalima, A. Frebel
semanticscholar +1 more source
Chemical sensitivity to the ratio of the cosmic-ray ionization rates of He and H2 in dense clouds [PDF]
, 2006 Aim: To determine whether or not gas-phase chemical models with homogeneous and time-independent physical conditions explain the many observed molecular abundances in astrophysical sources, it is crucial to estimate the uncertainties in the calculated ...
Baldwin +24 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 ...
D.G. Lambas, P. B. Tissera
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DETAILED CHEMICAL ABUNDANCES IN THE r-PROCESS-RICH ULTRA-FAINT DWARF GALAXY RETICULUM 2 [PDF]
, 2016 The ultra-faint dwarf (UFD) galaxy Reticulum 2 (Ret 2) was recently discovered in images obtained by the Dark Energy Survey. We have observed the four brightest red giants in Ret 2 at high spectral resolution using the Michigan/Magellan Fiber System.
I. Roederer +12 more
semanticscholar +1 more source
The origin and abundances of the chemical elements [PDF]
Reviews of Modern Physics, 1975 A NATO Advanced Studies Institute on the Origins and Abundances of the Chemical Elements was held at the Institute of Astronomy, Cambridge, England from 23 July to 9 August 1974. The problems discussed there are the basis for this review. Three major areas can be identified.
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