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New Rare Earth Element Abundance Distributions for the Sun and Five R-Process-Rich Very Metal-Poor Stars
(2009-05)
We have derived new abundances of the rare earth elements Pr, Dy, Tm, Yb, and Lu for the solar photosphere and for five very metal-poor, neutron-capture r-process-rich giant stars. The photospheric values for all five ...
Detection of the Second r-Process Peak Element Tellurium in Metal-Poor Stars
(2012-03)
Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, ...
The Abundances Of Neutron-Capture Species In The Very Metal-Poor Globular Cluster M15: A Uniform Analysis Of Red Giant Branch And Red Horizontal Branch Stars
(2011-06)
The globular cluster M15 is unique in its display of star-to-star variations in the neutron-capture elements. Comprehensive abundance surveys have been previously conducted for handfuls of M15 red giant branch (RGB) and ...
Metallicity And Alpha-Element Abundance Measurement In Red Giant Stars From Medium-Resolution Spectra
(2008-08)
We present a technique that applies spectral synthesis to medium-resolution spectroscopy (MRS; R similar to 6000) in the red (6300 angstrom < lambda < 9100 angstrom) to measure [Fe/H] and [alpha/Fe] of individual red giant ...
CS 22964-161: A Double-Lined Carbon- And S-Process-Enhanced Metal-Poor Binary Star
(2008-04)
A detailed high-resolution spectroscopic analysis is presented for the carbon-rich low-metallicity Galactic halo object CS 22964-161. We have discovered that CS 22964-161 is a double-lined spectroscopic binary and have ...
Improved Ti II Log(gf) Values and Abundance Determinations in the Photospheres of the Sun and Metal-Poor Star HD 84937
(2013-10)
Atomic transition probability measurements for 364 lines of Ti II in the UV through near-IR are reported. Branching fractions from data recorded using a Fourier transform spectrometer (FTS) and a new echelle spectrometer ...
Europium, Samarium, And Neodymium Isotopic Fractions In Metal-Poor Stars
(2008-03)
We have derived isotopic fractions of europium, samarium, and neodymium in two metal-poor giants with differing neutron-capture nucleosynthetic histories. These isotopic fractions were measured from new high-resolution (R ...
The End Of Nucleosynthesis: Production Of Lead And Thorium In The Early Galaxy
(2009-06)
We examine the Pb and Th abundances in 27 metal-poor stars (-3.1 < [Fe/H] < -1.4) whose very heavy metal (Z > 56) enrichment was produced only by the rapid (r-) nucleosynthesis process. New abundances are derived from ...
Improved Line Data for the Swan System (Cc)-C-12-C-13 Isotopologue
(2014-03)
We present new, accurate predictions for rotational line positions, excitation energies, and transition probabilities of the (CC)-C-12-C-13 isotopologue Swan d(3)Pi-a(3)Pi system 0-0, 0-1, 0-2, 1-0, 1-1, 1-2, 2-0, 2-1, and ...
Potassium In Globular Cluster Stars: Comparing Normal Clusters To The Peculiar Cluster NGC 2419
(2013-05)
Two independent studies recently uncovered two distinct populations among giants in the distant, massive globular cluster (GC) NGC 2419. One of these populations has normal magnesium (Mg) and potassium (K) abundances for ...