Heavy elements in the 2000-3000 A range of four AP stars.

Abstract

The long wavelength range of IUE has been examined in a search for heavy elements in four chemically peculiar stars of CP2 subgroup. Pb II 2203.53 appears to be present and a lead abundance higher than the solar one is derived for HD 188041 and HD 201601. No firm indication of the presence of Th II and U II can be established in the four program stars, while a great overabundance of these two elements had been previously derived by Severny and Liubimkov (1986) from the analysis of the same spectral range in 73 Dra, a CP star that belongs to the Sr-Cr-Eu subgroup.