453 citations · 2.3k across the 22 of their papers we have counts for
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The Barium Isotopic Abundance in the Metal-Poor Star HD140283
R. Collet, M. Asplund, P. E. Nissen
We derive the mixture of odd to even barium isotopes in the atmosphere of the metal-poor subgiant HD140283 from the analysis of the Ba II transition at 455.4 nm in a high-resolutio…
Sulphur and zinc abundances in Galactic halo stars revisited
P. E. Nissen, C. Akerman, M. Asplund +4
High resolution UVES spectra of 40 main-sequence stars with -3.3 < [Fe/H] < -1.0 are used to derive S, Fe and Zn abundances from lines in the 400 - 950 nm region. For one star we a…
Oxygen abundances in metal-poor subgiants as determined from [O I], O I and OH lines
A. E. García Pérez, M. Asplund, F. Primas +2
The debate on the oxygen abundances of metal-poor stars has its origin in contradictory results obtained using different abundance indicators. To achieve a better understanding of…
Lithium isotopic abundances in metal-poor halo stars
Martin Asplund, David L. Lambert, Poul Erik Nissen +2
Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances. The derived 1D, n…
Abundances in giant stars of the globular cluster NGC 6752
David Yong, Frank Grundahl, Poul Erik Nissen +2
Recent theoretical yields and chemical evolution models demonstrate that intermediate-mass AGB stars cannot reproduce the observed abundance distributions of O, Na, Mg, and Al. As…
The [Zn/Fe] -- [Fe/H] trend for disk and halo stars
Y. Q. Chen, P. E. Nissen, G. Zhao
Zn abundances, derived from a model atmosphere analysis of the 6362.35 A ZnI line, are presented for 44 thin disk, 10 thick disk and 8 halo dwarf stars in the metallicity range -1.…