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arXiv · astro-ph/0103481

Behavior of Sulfur Abundances in Metal-Poor Giants and Dwarfs

M. Takada-Hidai·Y. Takeda·S. Sato·S. Honda·K. Sadakane·S. Kawanomoto·W. L. W. Sargent·L. Lu·T. A. Barlow
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Abstract

LTE and NLTE abundances of sulfur in 6 metal-poor giants and 61 dwarfs (62 dwarfs, including the Sun) were explored in the range of -3 \lsim [Fe/H] \lsim $+0.5$ using high-resolution, high signal-to-noise ratio spectra of the \SI 8693.9 Åand 8694.6 Ålines observed by us and measured by \Francois (1987, 1988) and Clegg et al. (1981). NLTE effects in S abundances are found to be small and practically negligible. The behavior of [S/Fe] vs. [Fe/H] exhibits a linear increasing trend without plateau with decreasing [Fe/H]. Combining our results with those available in the literature, we find that the slope of the increasing trend is -0.25 in the NLTE behavior of [S/Fe], which is comparable to that observed in [O/Fe]. The observed behavior of S may require chemical evolution models of the Galaxy, in which scenarios of hypernovae nucleosynthesis and/or time-delayed deposition into interstellar medium are incorporated.

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M. Takada-Hidai, Y. Takeda, S. Sato, S. Honda, K. Sadakane, S. Kawanomoto, W. L. W. Sargent, L. Lu, T. A. Barlow. 2002-03-14. Behavior of Sulfur Abundances in Metal-Poor Giants and Dwarfs. https://doi.org/10.1086/340748

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