1ST RESULTS FROM THE GODDARD HIGH-RESOLUTION SPECTROGRAPH - ELEMENTAL ABUNDANCES IN THE DIFFUSE CLOUDS TOWARD ZETA-PERSEI

We present an analysis of high-resolution (3.5 km s-1) observations of ultraviolet interstellar absorption lines of dominant ion stages arising in the diffuse clouds (5 less-than-or-equal-to upsilon. less-than-or-equal-to 20 km s-1) toward zeta-Per (HD 24912; O7 IIInf) obtained with the Goddard High-Resolution Spectrograph (GHRS). We report a detection of the weak intersystem line of C II] lambda-2325 (W-lambda = 1.42 +/- 0.41 m angstrom). For C, O, and Mg we are able to derive column densities from both weak lines and the damping wings of strongly saturated lines. For Mg, the derived column densities differ by a factor 3. The UV absorption-line measurements have become so accurate that the interpretations are now limited by inaccuracies in atomic f-values and our knowledge of solar abundances. Comparison of apparent column densities profiles, N(a)(upsilon), between lightly depleted (e.g., O I, Zn II) and heavily depleted (e.g., Cr II, Fe II) species indicates a transition from substantial depletions at upsilon. almost-equal-to 7.5 km s-1 to a decrease in depletion of a factor 2 or more for 7.5 < upsilon. less-than-or-equal-to 20 km s-1. This processing may be related to the proximity of the cloud(s) to the H II region surrounding zeta-Per.