Abstract
We discuss oxygen abundances derived from (O ) λ6300 and the O triplet in stars spanning a wide range in chromo- spheric activity level, and show that these two indicators yield increasingly discrepant results with higher chromospheric/coronal activity measures. While the forbidden and permitted lines give fairly consistent results for solar-type disk dwarfs, spuriously high O triplet abundances are observed in young Hyades and Pleiades stars, as well as in individual components of RS CVn bi- naries (up to 1.8 dex). The distinct behaviour of the (O )-based abundances which consistently remain near-solar suggests that this phenomenon mostly results from large departures from LTE affecting the O triplet at high activity level that are currently unaccounted for, but also possibly from a failure to adequately model the atmospheres of K-type stars. These results suggest that some caution should be exercised when interpreting oxygen abundances in active binaries or young open cluster stars.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.