Intermediate-band photometry of late-type stars III. The Geneva Observatory (GO) photometric system.

The Geneva Observatory (GO) photometric system for late-type stars, combined with (R,I) photometry is found to be a useful supplement to results obtained on the modified Stro' mgren system discussed in Papers I and II. Over the range of (R - I) from + 0W22 to + the values of the metal abundance parameter m2 in the GO system is related to M1 m2 + 0.60 and the relation derived in Paper II can be applied with some accuracy; [Fe/Hj aM5- 2.50 where a = 19 - 35(R - I). The accuracy of this relation is tested with extensive lists of spectrographic abundance results for G and K stars. Some individual stars, especially metal-rich objects, observed on the GO system are also discussed. The purpose of this investigation was to examine the possibility that observations on the GO system could be used to supplement those on the modified Str6mgren system, described in Papers I and II, in studies of the correlation between metal abundance and kinematics of stars. Key words: photometry-GO photometric system-late-type stars-metal abundances