Analysis of elemental abundances in the atmospheres of three Hyades red giants

Model atmospheres are fitted to spectroscopic data in order to analyze the elemental abundances in the atmospheres of three red giants in the Hyades c luster. The three stars have almost identical chemical compositions, with i ron-group elements slightly overabundant compared to the salar values-a pat tern that is typical of Hyades dwarfs. The overabundances of the light elem ents Na, Al, and Si are virtually equal to those observed for held giants. No enrichment in rare-earth elements relative to iron was found, in shaly c ontrast to field giants. It is concluded that these discrepancies are due t o the age difference between the two groups of stars, which have resulted i n different degrees of convective overshooting, (C) 2000 MAIK "Nauka/Interp eriodica".