Ultraviolet extinction in the Small Magellanic Cloud.

Abstract

The considered investigation is concerned with the determination of the UV extinction curve in the Galaxy on the basis of the spectra of stars in the SMC obtained with the aid of the International Ultraviolet Explorer. The determination rests on the comparison of the observed spectral energy distribution of pairs of similar stars with different extinctions. Since extinction, as indicated by the color excess E(B-V), is rather small in the SMC, special care must be exercised in chosing stars as similar as possible. Uncertainties in the spectral classification and in the photometry of these stars result in large uncertainties in the extinction curve. The presented results are, therefore, still preliminary and must be confirmed by the study of more stars.