Results 21 to 30 of about 25,571 (294)
DISCOVERY OF TWO LITHIUM CEPHEIDS IN THE GALAXY
Odessa Astronomical Publications, 2017 We report about the discovery of two lithium Cepheids in the Galaxy, based on observations made with the echelle spectrograph of the Apache Point Observatory. We have used high- resolution, high signal-to-noise spectra to determine abundances of chemical
V. V. Kovtyukh +2 more
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New Keck Observations of Lithium in Very Metal-poor Stars [PDF]
, 2005 Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite Li plateau ...
Boesgaard, Ann Merchant +2 more
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Cool stars in NGC 2547 and pre main sequence lithium depletion [PDF]
, 2003 We present the results of a spectroscopic survey of X-ray selected, low-mass candidate members of the young open cluster NGC 2547. Using a combination of photometry, spectroscopic indices and radial velocities we refine our candidate list and then use ...
Jeffries, R. D +3 more
core +2 more sources
Frontiers in Astronomy and Space Sciences, 2021 A non-local and time-dependent theory of convection was briefly described. This theory was used to calculate the structure of solar convection zones, the evolution of massive stars, lithium depletion in the atmosphere of the Sun and late-type dwarfs, and
Da-run Xiong
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Rotation and lithium abundance of solar-analog stars. Theoretical analysis of observations [PDF]
, 2010 Rotational velocity, lithium abundance, and the mass depth of the outer convective zone are key parameters in the study of the processes at work in the stellar interior, in particular when examining the poorly understood processes operating in the ...
Alexander +34 more
core +1 more source
Ultra-lithium-deficient halo stars [PDF]
Proceedings of the International Astronomical Union, 2009 AbstractWhile most warm halo dwarfs show lithium abundances at the level of the Spite Plateau, a small number (~5%) have undetectable lithium lines. The existence of these stars has long raised questions when interpreting the plateau abundances: are they an extreme example of a depletion mechanism that has affected the plateau stars, or do they have an
Lisa M. Elliott, Sean G. Ryan
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, 2012 We derive atmospheric parameters and lithium abundances for 671 stars and include our measurements in a literature compilation of 1381 dwarf and subgiant stars. First, a "lithium desert" in the effective temperature (Teff) versus lithium abundance (A_Li)
Fish, J. R. +3 more
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Lithium abundance in a turnoff halo star on an extreme orbit [PDF]
, 2015 The lithium abundance in turnoff stars of the old population of our Galaxy is remarkably constant in the metallicity interval -2.8\textless{}[Fe/H] \textless{}-2.0, defining a plateau.
Bonifacio, Piercarlo +3 more
core +5 more sources
Lithium in stars with exoplanets [PDF]
Proceedings of the International Astronomical Union, 2009 AbstractOur recent study of solar-type stars from the HARPS GTO sample provides highly accurate information with regard to Lithium abundances in stars with and without detected planets (Israelian et al. 2009). When the Li abundances of planet bearing stars are compared with the “single” stars, we find an excess of Li depletion in planet hosts with ...
openaire +1 more source
Odessa Astronomical Publications, 2017 Results of computations of the lithium statistical equilibrium in atmospheres of Teff = 6270, 5770, 5270 and lg g = 4.44 dwarfs of metallicities [μ] = -0, - 1, - 2, - 3 are discussed. It is shown that NLTE corrections are less then 0.1 dex for abundances
Ya. V. Pavlenko, L. A. Yakovina
doaj +1 more source