Abundancias químicas de estrellas anómalas de Helio

LÓPEZ GARCÍA, Z.; MALARODA, S. M.; LEONE, F.; ALONSO, M. S

San Juan, Argentina

Congreso; Asociación Argentina de Astronomía; 1997

Asociacion Argentina de Astronomía

Elemental abundances of Si, Cr and Fe are obtained for a sample of Helium abnormal (He-rich and He-weak), normal and peculiar stars of the Silicon group, using REOSC echelle spectrograms obtained at CASLEO. The atmospheric parameters Teff and log g were derived from the Stromgren photometry according to the grid of Moon and Dworetsky as coded by Moon. Comparing with the Sun, Silicon shows a normal abundance in all stars except in the two Silicon stars where is overabundant; Cr is overabundant by factors that vary between 10 and 100, except in the normal star where is solar; Fe is lightly underabundant or overabundant in all stars.