Results 101 to 110 of about 226,407 (198)
The First Chemical Census of the Milky Way’s Nuclear Star Cluster
The Astrophysical Journal LettersAn important step in understanding the formation and evolution of the nuclear star cluster (NSC) is to investigate its chemistry and chemical evolution. Additionally, exploring the NSC’s relationship to the other structures in the Galactic center and the
Govind Nandakumar +6 more
doaj +1 more source
Tracking the Chemical Evolution of Hydrocarbons Through Carbon Grain Supply in Protoplanetary Disks
The Astrophysical JournalThe gas present in planet-forming disks typically exhibits strong emission features of abundant carbon and oxygen molecular carriers. In some instances, protoplanetary disks show an elevated C/O ratio above interstellar values, which leads to a rich ...
Eshan Raul +2 more
doaj +1 more source
Chemical Abundances in SFG and DLA
, 2005 We investigate the chemical abundances of local star-forming galaxies which cause Damped Lyman Alpha lines. A metallicity versus redshift diagram is constructed, on which the chemical abundances of low-redshift star-forming galaxy populations are compared with those of high-redshift Damped Lyman Alpha systems.
Schulte-Ladbeck, Regina E. +2 more
openaire +2 more sources
What Can We Learn from the Nitrogen Abundance of High-z Galaxies?
The Astrophysical JournalWe present measurements of the gas-phase oxygen and nitrogen abundances obtained by applying the direct method to JWST NIRspec R ∼ 1000 spectroscopy for six galaxies at redshift greater than 3.
Massimo Stiavelli +11 more
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The Sunburst Arc with JWST. III. An Abundance of Direct Chemical Abundances
The Astrophysical JournalAbstract We measure the gas-phase abundances of the elements He, N, O, Ne, S, Ar, and Fe in an individual H ii region known to be leaking Lyman-continuum photons in the Sunburst Arc, a highly magnified galaxy at redshift z = 2.37. We detect the temperature-sensitive auroral lines [S ii] λλ4070, 4076, [O iii] λ4363, [S ...
Brian Welch +13 more
openaire +3 more sources
Novae: An Important Source of Lithium in the Galaxy
The Astrophysical JournalThe source of the Galactic lithium (Li) has long been a puzzle. With the discovery of Li in novae, extensive research has been conducted. However, there still exists a significant disparity between the observed abundance of Li in novae and the existing ...
Jun Gao +6 more
doaj +1 more source
Analysis of the Internal Radial Gradient of Chemical Abundances in Spiral Galaxies from CALIFA
The Astrophysical JournalThe study of chemical evolution is of paramount importance for understanding the evolution of galaxies. Models and observations propose an inside-out mechanism in the formation of spiral galaxy disks, implying a negative radial gradient of elemental ...
A. F. S. Cardoso +3 more
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Modeling the Ages and Chemical Abundances of Elliptical Galaxies
The Astrophysical JournalSpectroscopic studies of elliptical galaxies show that their stellar population ages, mean metallicity, and α enhancement traced by [Mg/Fe] all increase with galaxy stellar mass or velocity dispersion.
Nicole Marcelina Gountanis +5 more
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The Astrophysical JournalGrouping stars by chemical similarity has the potential to reveal the Milky Way’s evolutionary history. The APOGEE stellar spectroscopic survey has the resolution and sensitivity for this task.
Catherine Manea +11 more
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The Astronomical JournalThe Open Cluster Chemical Abundances and Mapping (OCCAM) survey seeks to curate a large, comprehensive, uniform dataset of open clusters and member stars to constrain key Galactic parameters.
Jonah M. Otto +20 more
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