Metallicity function of red giants

For a sample of red giants comprising about 2000 stars, the distributions of metallicity [Fe/H] are given. It is shown that they cannot be described by a gaussian one in the sense that the normal-law hypothesis turns out to be statistically insignificant if the alternative is a hypothesis that the distribution is a sum of two normal curves. The center of the distributions of giants in both galactic poles is found to demonstrate a statisticaly significant gap similar to the one found earlier for the main-sequence stars. The implications of the metallicity distribution properties for the problems of the chemical evolution of the galactic disk are discussed