Results 11 to 20 of about 63,603 (275)

Solar and stellar photospheric abundances

Living Reviews in Solar Physics, 2016
The determination of photospheric abundances in late-type stars from spectroscopic observations is a well-established field, built on solid theoretical foundations.
Carlos Allende Prieto
doaj   +5 more sources

Stellar Iron Abundances: non-LTE Effects [PDF]

The Astrophysical Journal, 1999
We report new statistical equilibrium calculations for Fe I and Fe II in the atmosphere of Late-Type stars. We used atomic models for Fe I and Fe II having respectively 256 and 190 levels, as well as 2117 and 3443 radiative transitions.
Anstee S. D., Bell R. A., Bruls J. H. M. J., Carter W. W., Cayrel de Strobel G., Cayrel R., Cayrel R., F. Thevenin, Feltzing S., Foy R., Fuhrmann K., Gigas D., Gurtovenko E. A., Holweger H., Holweger H., Rutten R. J., Severino G., Steenbock W., T. P. Idiart, Takeda Y., Thevenin F., Thevenin F., Zhao G.   +22 more
core   +5 more sources

On the Hunt for the Origins of the Orphan–Chenab Stream: Detailed Element Abundances with APOGEE and Gaia

The Astrophysical Journal, 2023
Stellar streams in the Galactic halo are useful probes of the assembly of galaxies like the Milky Way. Many tidal stellar streams that have been found in recent years are accompanied by a known progenitor globular cluster or dwarf galaxy.
Keith Hawkins, Adrian M. Price-Whelan, Allyson A. Sheffield, Aidan Z. Subrahimovic, Rachael L. Beaton, Vasily Belokurov, Denis Erkal, Sergey E. Koposov, Richard R. Lane, Chervin F. P. Laporte, Christian Nitschelm   +10 more
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The Metallicity and Distance of Leo A from Blue Supergiants

The Astrophysical Journal, 2023
We have obtained high-quality spectra of blue supergiant candidates in the dwarf irregular galaxy Leo A with the Low Resolution Imaging Spectrometer at the Keck I telescope.
Miguel A. Urbaneja, Fabio Bresolin, Rolf-Peter Kudritzki   +2 more
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Chemical Analysis of the Brightest Star of the Cetus II Ultrafaint Dwarf Galaxy Candidate

The Astrophysical Journal, 2023
We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra.
K. B. Webber, T. T. Hansen, J. L. Marshall, J. D. Simon, A. B. Pace, B. Mutlu-Pakdil, A. Drlica-Wagner, C. E. Martínez-Vázquez, M. Aguena, S. S. Allam, O. Alves, E. Bertin, D. Brooks, A. Carnero Rosell, J. Carretero, L. N. da Costa, J. De Vicente, P. Doel, I. Ferrero, D. Friedel, J. Frieman, J. García-Bellido, G. Giannini, D. Gruen, R. A. Gruendl, S. R. Hinton, D. L. Hollowood, K. Honscheid, K. Kuehn, J. Mena-Fernández, F. Menanteau, R. Miquel, R. L. C. Ogando, M. E. S. Pereira, A. Pieres, A. A. Plazas Malagón, E. Sanchez, B. Santiago, J. Allyn Smith, M. Smith, E. Suchyta, G. Tarle, C. To, N. Weaverdyck, B. Yanny   +44 more
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Theoretical Predictions of Surface Light Element Abundances in Protostellar and Pre-Main Sequence Phase

Frontiers in Astronomy and Space Sciences, 2021
Theoretical prediction of surface stellar abundances of light elements–lithium, beryllium, and boron–represents one of the most interesting open problems in astrophysics.
E. Tognelli, E. Tognelli, S. Degl’Innocenti, S. Degl’Innocenti, P. G. Prada Moroni, P. G. Prada Moroni, L. Lamia, L. Lamia, L. Lamia, R. G. Pizzone, A. Tumino, A. Tumino, C. Spitaleri, C. Spitaleri, A. Chiavassa   +14 more
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ACTINIUM ABUNDANCES IN STELLAR ATMOSPHERES

Odessa Astronomical Publications, 2021
This paper presents a study of radioactive  actinium in the atmospheres of stars located in galaxies with different chemical evolution history – namely, Przybylski's Star (HD 101065) in the Milky Way and the red supergiant PMMR27 in the Small Magellanic Cloud; it also reports the findings of the previous research of the red supergiant RM 1-667 in the ...
V. Yushchenko, V. Gopka, A.V. Yushchenko, A. Shavrina, Ya. Pavlenkо, S. Vasil’eva   +5 more
openaire   +4 more sources

Robust Data-driven Metallicities for 175 Million Stars from Gaia XP Spectra

The Astrophysical Journal Supplement Series, 2023
We derive and publish data-driven estimates of stellar metallicity [M/H] for ∼175 million stars with low-resolution XP spectra published in Gaia DR3.
René Andrae, Hans-Walter Rix, Vedant Chandra   +2 more
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Stellar Abundances in Local Group Galaxies [PDF]

Highlights of Astronomy, 2005
AbstractHere we describe some of our latest results from measuring detailed abundances in Local Group dwarf galaxies with the VLT. Combining spectroscopic abundances with Color-Magnitude diagrams allows the effective measurement of detailed chemical evolution with time in these galaxies.
Tolstoy, Eline, Venn, Kim
openaire   +2 more sources

Intriguing Revelations from Lithium, Beryllium, and Boron

The Astrophysical Journal, 2023
This is a report on some highlights of research on the rare light elements, lithium (Li), beryllium (Be), and boron (B), that were presented at my Henry Norris Russell Lecture in 2020 January.
Ann Merchant Boesgaard
doaj   +1 more source