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Heavy-Element Dispersion In The Metal-Poor Globular Cluster M92
(2011-07)
Dispersion among the light elements is common in globular clusters (GCs), while dispersion among heavier elements is less common. We present detection of r-process dispersion relative to Fe in 19 red giants of the metal-poor ...
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 ...
Improved V II Log(gf) Values, Hyperfine Structure Constants, and Abundance Determinations in the Photospheres of the Sun and Metal-Poor Star HD 84937
(2014-10)
New experimental absolute atomic transition probabilities are reported for 203 lines of VII. Branching fractions are measured from spectra recorded using a Fourier transform spectrometer and an echelle spectrometer. The ...
Transition Probabilities Of Astrophysical Interest In The Niobium Ions Nb+ And Nb2+
(2010)
Aims. We attempt to derive accurate transition probabilities for astrophysically interesting spectral lines of Nb II and Nb III and determine the niobium abundance in the Sun and metal-poor stars rich in neutron-capture ...
Chemical Compositions Of Thin-Disk, High-Metallicity Red Horizontal-Branch Field Stars
(2012-07)
We present a detailed abundance analysis and atmospheric parameters of 76 stars from a survey to identify field Galactic red horizontal-branch (RHB) stars. High-resolution echelle spectra (R similar or equal to 60,000, S/N ...
The Magnesium Isotopologues of MgH in the A(2)Pi-X-2 Sigma(+) System
(2013-08)
Using laboratory hollow cathode spectra we have identified lines of the less common magnesium isotopologues of MgH, (MgH)-Mg-25 and (MgH)-Mg-26, in the A(2)Pi-X-2 Sigma(+) system. Based on the previous analysis of (MgH)-Mg-24, ...
Hubble Space Telescope Near-Ultraviolet Spectroscopy Of The Bright CEMP-No Star BD+44 Degrees 493
(2014-07)
We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the extremely metal-poor star BD+44 degrees 493 a ninth magnitude subgiant with [Fe/H] = -3.8 and enhanced carbon, based on data ...
The Ubiquity Of The Rapid Neutron-Capture Process
(2010-12)
To better characterize the abundance patterns produced by the r-process, we have derived new abundances or upper limits for the heavy elements zinc (Zn, Z = 30), yttrium (Y, Z = 39), lanthanum (La, Z = 57), europium (Eu, ...
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, ...
Line Lists for the A(2)Pi-X-2 Sigma(+) (Red) and B-2 Sigma(+)-X-2 Sigma(+) (Violet) Systems of Cn, (Cn)-C-13-N-14, and (Cn)-C-12-N-15, and Application To Astronomical Spectra
(2014-10)
New red and violet system line lists for the CN isotopologues (CN)-C-13-N-14 and (CN)-C-12-N-15 have been generated. These new transition data are combined with those previously derived for (CN)-C-12-N-14, and applied to ...