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Evolution of Population II stars
Astronomy and Astrophysics Review, 1998The current knowledge of the evolution of Population II stars, as observed in galactic halos and globular clusters, is outlined. The recent theoretical results provided by an improved physical understanding of the stars are reported, with a particular emphasis upon those stellar evolutionary phases which are the keystones of the interpretation of ...
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Lithium in Population II Stars
1992NEW data about dwarfs : a few more metal-poor dwarfs have been observed for lithium at the CAT + CES at La Silla (ESO). These new results, together with a few new measurements in the literature show again a constant lithium abundance, confirming the trend previously found (the plateau).
F. Spite, M. Spite, R. Cayrel, S. Huille
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Accretion of Heavy Elements on Population II Stars
Publications of the Astronomical Society of Japan, 1957Abstract The effect of accretion of heavy elements on spectral appearance of population II stars, especially of globular cluster stars, are investigated in detail. It is shown to be implausible to explain the existence of these heavy elements by the accretion from outside.
Hisao Takebe, Naoyuki Matsunami
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Radial Velocities of Late-Type Population II Stars
International Astronomical Union Colloquium, 1984AbstractEarly radial-velocity work on high-velocity stars has been summarized. Present samples of such stars have been reviewed. Selection methods and sample bias have been discussed. Spectroscopic as well as photometric methods have been examined. In order to find a reasonably bias-free sample of late-type stars of Population II, photometric survey ...
A. Ardeberg, H. Lindgren
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Enhanced ?-elements and He-burning Population II stars
Astrophysics and Space Science, 1989Spectroscopic analysis of Population II stars indicates that oxygen and other α-elements appear to be overabundant with respect to iron (Sneden, 1985; Grattonet al., 1986; Gustafsson, 1987; Gratton, 1987; Gratton and Ortolani, 1989). By use of the Los Alamos Tapes Library, new opacities for Population II stars have been computed, including oxygen, neon,
D. Bencivenni +3 more
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Spectra of Population II Cepheid Variable Stars
1958The physical properties of the population II cepheids have been studied using the following material: photoelectric observations of Arp, low dispersion spectra of Joy, high dispersion spectra taken by Sanford and Abt, and numerous moderate dispersion spectra obtained by the author. Radial velocity curves for ten cepheids are shown.
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The Cepheids of Population II and Related Stars
Publications of the Astronomical Society of the Pacific, 2002The Type II Cepheids include most intrinsic variables with periods between 1 and about 50 days, except for the classical Cepheids and the shortest semiregular variables of type M. The Type II Cepheids may be divided in groups by period, such that the stars with periods beween 1 and 5 days (BL Her class), 10-20 days (W Vir class), and greater than 20 ...
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A B-type Star of Population II
Publications of the Astronomical Society of the Pacific, 1954Jesse L. Greenstein, James Cuffey
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