Results 91 to 100 of about 226,407 (198)

THE CHEMICAL ABUNDANCES OF ATMOSPHERES OF K GIANT STARS

Odessa Astronomical Publications, 2017
The abundances of 18 cool giant stars in Vicinity of Sun have been determinated. This determination was made by using the method of model atmospheres. It should be noted that almost all elements show discrepancies in abundances determined for absorption ...
N. S. Komarov, N. Yu. Basak, T. I. Gorbaneva, L. E. Kantsen   +3 more
doaj   +1 more source

The nature of Long-GRB host galaxies from chemical abundances

, 2010
Gamma-ray bursts (GRBs) are the most energetic events after the Big Bang and they have been observed up to very high redshift. By means of measures of chemical abundances now available for the galaxies hosting such events,thought to originate from the ...
Akerman, Bell, Bissaldi, Boissier, Bradamante, Calura, Calura, Calura, Campisi, Castro Cerón, Cescutti, Chary, Chen, Chiappini, Chiappini, Chisari, Cowie, F. Matteucci, François, Fynbo, Fynbo, Galama, Graham, Greiner, Hjorth, Hou, Iwamoto, J. Yin, Jakobsson, Kistler, Lamb, Lanfranchi, Lapi, Levesque, Levesque, Li, Liang, Mannucci, Mao, Matteucci, Matteucci, Matteucci, Matteucci, Micha▯owski, Møller, Naab, Nuza, Padovani, Pian, Pipino, Pipino, Pipino, Pontzen, Prochaska, Prochaska, Rau, Romano, Romano, Salpeter, Salvaterra, Savaglio, Savaglio, Schmidt, Shapley, Svensson, Tanvir, van den Hoek, Wolf, Wolfe, Woosley, Woosley, Woosley, X. L. Fan, Yin, Yin, Yoon, Zwaan   +76 more
core   +1 more source

Rapid Chemical Enrichment by Intermittent Star Formation in GN-z11

The Astrophysical Journal Letters
We interpret the peculiar supersolar nitrogen abundance recently reported by the James Webb Space Telescope observations for GN-z11 ( z = 10.6) using our state-of-the-art chemical evolution models.
Chiaki Kobayashi, Andrea Ferrara
doaj   +1 more source

Determination of Abundances of Chemical Elements in Open Star Clusters of the Galaxy

Open Astronomy, 2016
Spectroscopic determinations of the relative abundances of chemical elements produced in different nuclear-synthesis processes, [el/Fe], are collected for 90 open star clusters of the Galaxy using data from 109 papers published between 1991 and 2015 ...
Gozha M. L., Koval’ V. V., Marsakov V. A.   +2 more
doaj   +1 more source

Chemical Doppelgangers in GALAH DR3: The Distinguishing Power of Neutron-capture Elements among Milky Way Disk Stars

The Astrophysical Journal
The observed chemical diversity of Milky Way stars places important constraints on Galactic chemical evolution and the mixing processes that operate within the interstellar medium. Recent works have found that the chemical diversity of disk stars is low.
Catherine Manea, Keith Hawkins, Melissa K. Ness, Sven Buder, Sarah L. Martell, Daniel B. Zucker   +5 more
doaj   +1 more source

The Impact of Initial Composition on Massive Star Evolution and Nucleosynthesis

The Astrophysical Journal
We study the sensitivity of presupernova evolution and supernova nucleosynthesis yields of massive stars to variations of the initial composition. We use the solar abundances from Lodders, and compute two different sets of initial stellar compositions ...
Christopher West, Alexander Heger, Benoit Côté, Lev Serxner, Haoxuan Sun   +4 more
doaj   +1 more source

Noble Gas Planetology and the Xenon Clouds of Uranus

The Planetary Science Journal
Noble gases provide tracers of cosmic provenance that are accessible to a future Uranus atmospheric probe. Argon and krypton are expected to be well mixed on Uranus with respect to H _2 and He, although condensation at the winter pole may be possible ...
Kevin Zahnle
doaj   +1 more source

New Neutral–Neutral Pathways in the Chemistry of Silicon- and Sulfur-bearing Molecules in the Cold Interstellar Medium

The Astrophysical Journal
Silicon is the most abundant third-row element in space and plays a major role in interstellar dust as silicate particles. Furthermore, silicon is important for the formation of silicate dust in oxygen-rich AGB stars and in supernova remnants.
Samuel F. M. Costa, Márcio O. Alves, Sérgio Pilling, Jing Li, Breno R. L. Galvão   +4 more
doaj   +1 more source

Gaia FGK benchmark stars: Spectral library and abundances of α and Fe-peak elements of the third version

Astronomy & Astrophysics
Context. Accurate determination of the chemical abundances in stars plays a pivotal role in understanding stellar structure and evolution, nucleosynthesis, and the chemical enrichment history of the Milky Way.
Casamiquela L., Soubiran C., Jofré P., Vitali S., Blanco-Cuaresma S., Lagarde N., Slumstrup D., Heiter U., Palmerio J. T., Brouillet N., Elgueta S., Rojas–Arriagada A., Aguilera–Gómez C., Hernández–Araya I., Creevey O. L., Balaguer–Núñez L., Carrera R.   +16 more
doaj   +1 more source

Complete Survey of r-process Conditions: The (Un)robustness of the r-process(es)

The Astrophysical Journal
Heavy elements are synthesized by the r -process in neutron star mergers and potentially in rare supernovae linked to strong magnetic fields. Expensive hydrodynamic simulations of these extreme environments are usually postprocessed to calculate the ...
Jan Kuske, Almudena Arcones, Moritz Reichert   +2 more
doaj   +1 more source