Based on extensive statistical-equilibrium calculations , we performed a non-LTE analysis of the K i 7699 equivalent-width data of metal-deficient stars for the purpose of clarifying the behavior of the photospheric potassium abundance in disk/halo stars .
While the resulting non-LTE abundance corrections turned out to be considerably large , amounting to 0.2–0.7 dex , their effect on the [ K/Fe ] vs. [ Fe/H ] relation is not very important , since these corrections do not show any significant metallicity dependence .
Hence , we again confirmed the results of previous LTE studies , that [ K/Fe ] shows a gradual systematic increase toward a lowered metallicity up to [ K/Fe ] \sim 0.3–0.5 at [ Fe/H ] \sim -1 to -2 , such as in the case of \alpha elements .