SIMBAD references

The main atmospheric parameters and abundances of the iron-group elements (vanadium, chromium, iron, cobalt and nickel) are determined for 62 red giant `clump' stars revealed in the Galactic field by the Hipparcos orbiting observatory. The stars form a homogeneous sample with the mean value of temperature T_eff= 4750±160K, of surface gravity log g = 2.41±0.26 and the mean value of metallicity [Fe/H] = -0.04±0.15dex. A Gaussian fit to the [Fe/H] distribution produces the mean <[Fe/H]> = -0.01 and dispersion σ_[Fe/H]= 0.08. The near-solar metallicity and small dispersion of σ_[Fe/H] of clump stars of the Galaxy obtained in this paper confirm the theoretical model of the Hipparcos clump by Girardi & Salaris. This suggests that nearby clump stars are (in the mean) relatively young objects, reflecting mainly the near-solar metallicities developed in the local disc during the last few Gyr of its history. We find iron-group element to iron-abundance ratios in clump giants to be close to solar.