Establish iron abundances [Fe/H] for Collinder 197, NGC 6649, and NGC 6709

Ascertain the iron abundance [Fe/H] of the open clusters Collinder 197, NGC 6649, and NGC 6709 by conducting homogeneous spectroscopic analyses or compiling vetted literature determinations, in order to enable more robust metallicity-based membership validation and comparisons across clusters.

Background

The metallicity analysis uses literature [Fe/H] values as references to assess membership and interpret lithium behavior across clusters. Where reliable literature metallicities exist, they support the validation of member lists and the paper of lithium–age relations.

For Collinder 197, NGC 6649, and NGC 6709, the authors report that no prior [Fe/H] measurements were found in the literature at the time of their paper, highlighting an unresolved need for metallicity determinations to strengthen future analyses involving these clusters.