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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 ...
M Dwarf Metallicities And Giant Planet Occurrence: Ironing Out Uncertainties And Systematics
(2014-08)
Comparisons between the planet populations around solar-type stars and those orbiting M dwarfs shed light on the possible dependence of planet formation and evolution on stellar mass. However, such analyses must control ...
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 ...
Is the Post-AGB Star SAO 40039 Mildly Hydrogen-Deficient?
(2011-08)
We have conducted an LTE abundance analysis for SAO 40039, a warm post-AGB star whose spectrum is known to show surprisingly strong He I lines for its effective temperature and has been suspected of being H-deficient and ...
Very Metal-Poor Stars in the Outer Galactic Bulge Found By the APOGEE Survey
(2013-04)
Despite its importance for understanding the nature of early stellar generations and for constraining Galactic bulge Formation models, at present little is known about the metal-poor stellar content of the central Milky ...
An In-Depth Spectroscopic Analysis Of The Blazhko Star Rr Lyrae I. Characterisation Of The Star: Abundance Analysis And Fundamental Parameters
(2010-09)
Context. The knowledge of accurate stellar parameters is a keystone in several fields of stellar astrophysics, such as asteroseismology and stellar evolution. Although the fundamental parameters can be derived from both ...
Rb-Rich Asymptotic Giant Branch Stars in the Magellanic Clouds
(2009-11)
We present high-resolution (R similar to 60,000) optical spectra of a carefully selected sample of heavily obscured and presumably massive O-rich asymptotic giant branch (AGB) stars in the Magellanic Clouds. We report the ...
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 ...
Elemental Abundances Of Solar Sibling Candidates
(2014-06)
Dynamical information along with survey data on metallicity and in some cases age have been used recently by some authors to search for candidates of stars that were born in the cluster where the Sun formed. We have acquired ...
Effects Of Rotationally Induced Mixing In Compact Binary Systems With Low-Mass Secondaries And In Single Solar-Type Stars
(2012-08)
Many population synthesis and stellar evolution studies have addressed the evolution of close binary systems in which the primary is a compact remnant and the secondary is filling its Roche lobe, thus triggering mass ...