Interstellar absorption lines in the spectra of theta-Crateris and 14Canum Venaticorum.
de Boer, K. S.; Grewing, M.; Bianchi, L.; Skuppin, R.
Germany, Italy
Abstract
High-resolution (≡0.2 Å) ultraviolet spectra of the two B9 stars θ Crateris (HD 100889) and 14 Canum Venaticorum (HD 113797) have been obtained with the IUE satellite. Since both are fast rotators interstellar absorption lines can easily be separated from the stellar features allowing a determination of the Mg I, Mg II, Fe II, Si II, and S II column densities. While both stars are roughly at the same distance from the Sun, the column densities towards θ Crt (l = 274°, b = 49°) are larger by roughly a factor of 30 than those to 14 CVn (l = 104°, b = 81°). From the Mg I/Mg II ratio the authors conclude that the gas temperature is high towards 14 CVn.