Results 11 to 20 of about 9,431 (248)
CHLORINE ABUNDANCES IN COOL STARS [PDF]
The Astronomical Journal, 2016 Chlorine abundances are reported in 15 evolved giants and one M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H$^{35}$Cl at 3.69851 $ $m. The high resolution L-band spectra were observed using the Phoenix infrared spectrometer on the Kitt Peak Mayall 4m telescope.
Z. G. Maas, C. A. Pilachowski, K. Hinkle
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Abundance analysis of Barium stars [PDF]
Research in Astronomy and Astrophysics, 2009 We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution Echelle spectra. The neutron capture process elements Y, Zr, Ba, La, Eu show obvious overabundance relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, including Na, Mg, Al,
Liu, G. Q., Liang, Y. C., Deng, L.
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Oxygen Abundances in Metal‐poor Stars [PDF]
The Astrophysical Journal, 2003 We present oxygen abundances derived from both the permitted and forbidden oxygen lines for 55 subgiants and giants with [Fe/H] values between -2.7 and solar with the goal of understanding the discrepancy in the derived abundances. A first attempt, using \teff{} values from photometric calibrations and surface gravities from luminosities, obtained ...
Fulbright, Jon. P., Johnson, Jennifer A.
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Abundances in Przybylski's star [PDF]
Monthly Notices of the Royal Astronomical Society, 2000 We have derived abundances for 54 elements in the extreme roAp star HD 101065. ESO spectra with a resolution of about 80 000, and S/N of 200 or more were employed. The adopted model has Teff=6600 K, and log(g)=4.2. Because of the increased line opacity and consequent low gas pressure, convection plays no significant role in the temperature structure ...
Cowley, Charles R. +5 more
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Nitrogen abundances in planet-harbouring stars [PDF]
Astronomy & Astrophysics, 2004 We present a detailed spectroscopic analysis of nitrogen abundances in 91 solar-type stars, 66 with and 25 without known planetary mass companions. All comparison sample stars and 28 planet hosts were analysed by spectral synthesis of the near-UV NH band at 3360 observed at high resolution with the VLT/UVES,while the near-IR NI 7468 was measured in
Ecuvillon, A. +5 more
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Abundances in cool evolved stars [PDF]
International Astronomical Union Colloquium, 1988 Nature has filled the upper right quadrant of the Hertzsprung-Russell diagram with more varieties of peculiar stars and odd chemical compositions than even our most speculative observers and theorists could dream up. To bring some structure to this vast subject I will categorize the phenomena we observe according to our model of stellar evolution ...
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Astronomy & Astrophysics, 2011 10 pages, accepted for publication in A& ...
Spite, M. +17 more
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Abundances in Stars with Exoplanets [PDF]
Symposium - International Astronomical Union, 2004 Extensive spectroscopic studies of stars with and without planets have concluded that stars hosting planets are significantly more metal-rich than those without planets. More subtle trends of different chemical elements begin to appear as the number of detected extrasolar planetary systems continues to grow.
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Abundances of Extremely Metal-poor Star Candidates [PDF]
The Astronomical Journal, 2004 We present chemical abundances for 110 stars identified in objective-prism surveys as candidates to be very metal-poor. The abundances are derived from high S/N, intermediate-resolution spectra obtained with the Keck Observatory Echelle Spectrometer and Imager.
Lai, David K. +3 more
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Abundances in hot evolved stars [PDF]
International Astronomical Union Colloquium, 1988 In the upper left corner of the HR-diagram various stars have been found that are clearly not members of the hydrogen main sequence. The majority of them lie to the left and below the main sequence, indicating that they are highly evolved stars close to the extinction of their thermonuclear power source and hence to rapid cooling towards the white ...
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