Observational constraints on potassium synthesis during the formation of stars of the Galactic disk

  title={Observational constraints on potassium synthesis during the formation of stars of the Galactic disk},
  author={Vladislav Shimansky and Ilfan F. Bikmaev and A. I. Galeev and N. N. Shimanskaya and D. V. Ivanova and N. A. Sakhibullin and Faig A. Musaev and G. A. Galazutdinov},
  journal={Astronomy Reports},
The non-LTE potassium abundances in the atmospheres of 33 Galactic-disk stars are derived and the parameters of the atmospheres of 23 of the stars are determined. Neglecting departures from LTE results in a systematic overestimation of the potassium abundances and an increase in their dispersion, even for differential analyses relative to the Sun. The non-LTE corrections are significant ((−0.2)–(−0.6) dex) and depend on the surface gravities and effective temperatures of the stars. The mean… Expand
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