The Luminosities of Late-Type Stars of Differing Metal Abundance

A technique is described which determines approximate luminosities of G- and K-type stars. It is based on narrow-band photometric observations of the Mg b4ines and the blue CN band, and upon broad-band observations of ultraviolet excess, (0.6), and the blanketing-free index, (B - V) . The technique may be applied to stars of normal as well as of low metal abundance, but in this paper special attention is given to stars of low metal abundance. The use of the technique in kinematic studies is illustrated by reference to stars in Sandage's list of newly discovered subdwarfs.