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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 ...
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 ...
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 ...
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 ...
Relationship Between Low And High Frequencies In Delta Scuti Stars: Photometric Kepler And Spectroscopic Analyses Of The Rapid Rotator KIC 8054146
(2012-11)
Two years of Kepler data of KIC 8054146 (delta Sct/gamma Dor hybrid) revealed 349 statistically significant frequencies between 0.54 and 191.36 cycles day(-1) (6.3 mu Hz to 2.21 mHz). The 117 low frequencies cluster in ...
VLT/FLAMES Spectroscopy Of Red Giant Branch Stars In The Carina Dwarf Spheroidal Galaxy
(2012-02)
Context. The ages of individual red giant branch stars can range from 1 Gyr old to the age of the Universe, and it is believed that the abundances of most chemical elements in their photospheres remain unchanged with time ...
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 ...