The parameters and abundances show excellent consistency across phase. The latter set of stars span periods between 1.5 and 68 days. Results from five or more phases are available for 52 of the program stars. Parameters and abundances have been derived for 435 Cepheids based on an analysis of 1127 spectra. Accordingly, not only main-sequence stars but also evolved red giant stars are usable for tracing the chemical evolution history of S and Zn in the regime of disk metallicity by using these lines. The finally resulting - and - relations for GK giants were confirmed to be in good agreement with those for FGK dwarfs, indicating that S and Zn abundances of red giants are reliably determinable from the S I 6757 and Zn I 6362 lines. It revealed that the S I 6757 feature is more reliable as an abundance indicator than S I 8694-5 for the case of red giants, because the latter suffers blending of unidentified lines. The non-LTE corrections for the S and Zn abundances derived from these lines turned out < 0.1(-0.2) dex for most cases and not very significant. Besides, similar abundance analysis was done for 160 FGK dwarfs to be used for comparison. Given this situation, we tried to establish the abundances of these elements for an extensive sample of 239 field GK giants (-0.8 < < +0.2), by applying the spectrum-fitting technique to S I 8694-5, S I 6757, and Zn I 6362 lines and by taking into account the non-LTE effect. However, regarding red giants having evolved off the main sequence, reliable abundance determinations of S and Zn seem to be difficult despite that a few studies have been reported so far. Sulfur and zinc are chemically volatile elements, which play significant roles as depletion-free tracers in studying galactic chemical evolution. Models are needed incorporating such effects as rotationally driven Standard model of stellar mixing is deficient and that new evolutionary The implication of these results is that the Of these effects are also present in the Li and CNO abundances of The ratio in these stars in subsolar with an average value of Of the stars show the effects of nuclear processing though to differentĭegrees: the stars are carbon deficient and nitrogen enhanced. The canonical interstellar disk value and the lithium abundances The lithium abundances are diluted in most stars with respect to.In good agreement with the ratios found in supergiants and giants The bright giants have ratios which are solar and are.The pertinent results of the present study This study was designed toĬomplement CNO abundance studies of supergiants and giants which bracket Giants have been determined based on high-resolution and high Stellar parameters and abundances for a sample of 38 F/U field bright
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