INTERSTELLAR ABSORPTION ALONG THE LINE OF SIGHT TO SIGMA-SCORPII USING COPERNICUS OBSERVATIONS

From Copernicus observations of σ Sco, 57 individual lines of 11 elements plus the molecular species H2 and CO were identified. By using a profile-fitting technique, rather than curves of growth, we were able to obtain column densities and Doppier b values for up to four separate components along this line of sight. Electron density in the major H I component was derived from the ohotoionization equilibrium of sulfur, obtaining, ne ≈ 0.3 cm-3. We also derived (with considerable uncertainty) the neutral hydrogen density in the same component using fine-structure excitation of O I. An H II component is also present in which the electron density was ne ≈ 20 cm-3. We calculated elemental depletions for the major H I components along this line of sight, as well as for an tions were different; however, the relative depletions (the element-to-element depletion patterns) were remarkably stable. As a by-product of this analysis, previously undetermined oscillator strengths for two Mn n lines were obtained: for 1162.017 Å,f ≈ 0.023 and for 1164.211 Å, f ≈ 0.0086.