Physical parameters for Population II stars.

Abstract

The observed energy distributions from the ultraviolet to the near-infrared for a number of Population II stars have been collected from the literature (Christensen, 1978; Cacciari, 1985) and have been compared with the Kurucz (1979) model atmospheres computed for different [M/H] ratios. Effective temperatures, surface gravities and apparent angular diameters have been obtained for those stars falling in the T_eff range covered by the Kurucz models. For each of these stars the results refer to that [M/H] value which permits the best reproduction of the observations according to a weighted LMS error criterion. The quality of the derived parameters is discussed, and comparisons with previous results cited in the literature are presented.