241 citations · 1.1k across the 18 of their papers we have counts for
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Iron-Peak Element Abundances in Warm Very Metal-Poor Stars
Christopher Sneden, Ann Merchant Boesgaard, John J. Cowan +3
We have derived new detailed abundances of Mg, Ca, and the Fe-group elements Sc through Zn (Z = 21-30) for 37 main sequence turnoff very metal-poor stars ([Fe/H] <= -2.1). We analy…
Atomic Transition Probabilities for Transitions of Si I and Si II and the Silicon Abundances of Several Very Metal-Poor Stars
E. A. Den Hartog, J. E. Lawler, C. Sneden +2
We report new measurements of branching fractions for 20 UV and blue lines in the spectrum of neutral silicon (Si I) originating in the 334 P, $^…
The R-Process Alliance: A Nearly Complete R-Process Abundance Template Derived from Ultraviolet Spectroscopy of the R-Process-Enhanced Metal-Poor Star HD 222925
Ian U. Roederer, James E. Lawler, Elizabeth A. Den Hartog +9
We present a nearly complete rapid neutron-capture process (r-process) chemical inventory of the metal-poor ([Fe/H] = -1.46 +/- 0.10) r-process-enhanced ([Eu/Fe] = +1.32 +/- 0.08)…
Atomic Transition Probabilities of Neutral Calcium
E. A. Den Hartog, J. E. Lawler, C. Sneden +3
The goals of this study are 1) to test the best theoretical transition probabilities for Ca I (a relatively light alkaline earth spectrum) from a modern ab initio calculation using…
Improved Atomic Transition Probabilities for UV and Optical Lines of Hf II and Determination of the Hf Abundance in Two Metal-Poor Stars
E. A. Den Hartog, J. E. Lawler, I. U. Roederer
We report new branching fraction measurements for 199 UV and optical transitions of Hf II. These transitions range in wavelength (wavenumber) from 2068- 6584 A (48322-15183 cm-1) a…
Detection of Pb II in the Ultraviolet Spectra of Three Metal-Poor Stars
Ian U. Roederer, James E. Lawler, Erika M. Holmbeck +8
We report the first detection of the Pb II line at 2203.534 Angstroms in three metal-poor stars, using ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on…