Another lithium-rich K giant - HD 30238

Abstract

The K giant HD 30238 is reported to show a strong feature due to Li I 6707 A, corresponding to a lithium abundance of log epsilon(Li) = 1.2 + or - 0.05. This star appears to be another example of a rare class of otherwise normal, low-mass K giants with unusually high lithium abundances. The C-12/C-13 isotope ratio in HD 30238 is approximately 26 + or - 4; this low value suggests that the star has developed a normal K giant convective envelope. The observed abundance of lithium in the spectrum of the star may be inconsistent with this low carbon isotope ratio. The abundance of lithium in low-mass stars on the red giant branch as a function of effective temperature suggests that lithium continues to be depleted from the convective envelope during evolution up the red giant branch. 31 refs.