CCD OBSERVATIONS OF ADDITIONAL INTERSTELLAR LINES IN STARS ASSOCIATED WITH THE VELA REMNANT AND ETA CARINAE NEBULOSITY

We have obtained CCD spectrograms with 2 pixel resolving power of 20 000 and signal-to-noise from about 100-300 of nine carefully selected stars in the Vela Remnant and seven stars in the Eta Carinae complex. The spectra cover the region from 3200 to 4400 angstrom thereby including features of Na I, Ti II, Ca I, CH+, and CH. In addition, lines of the r-process elements Eu II, Gd II, Ra II, and Th II have been searched for and not found. The behavior of each of the species is interesting. The Ti II lines indicate smaller depletions than in common diffuse clouds due to shock-induced evaporation of grains in Vela and either the contribution by ionized stellar winds or radiative evaporation of grains in Carina. Ca I is used to derive the electron density in two clouds which confirms the high hydrogen density previously observed in the clouds in front of HD 72350 and HD 72648. Interstellar Ca I at a velocity of -90 km s-1 was found in the close triple, HD 93160 and HD 93161EW. CH+ shows a wide range of strengths, presumably due to its origin in weak shocks which are not easy to recognize amid all the high-velocity gas in Vela and Carina. CH provides evidence for high H I density in certain clouds, confirming the values indicated by Ca I and by the excitation of the fine-structure lines of carbon from IUE spectrograms.