Intermediate band photometry of late-type stars. II. Some stellar groups.

Observations on the (R, I) system and a modified Stromgren system of members of six stellar groups are used to demonstrate the chemical homogeneity of some 70% or 80% of the members assigned to the groups on the basis of kinematics. The groups discussed are the Hyades, Wolf 630, Arcturus, Groombridge 1830, and Kapteyn's Star Groups as well as an anonymous group of a half dozen subdwarfs with (U, V) near (-150, -320) km/s. Standards for a previously described photometric system are extended, and additional F- and G-type standards for the (R, I) system are presented. A simple relation is derived for computing the Fe/H abundance ratio for most stars in the corrected (R-I) interval from +0.2 to +0.45 magnitude.