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We report on new GHRS/HST observations of the interstellar HI and DI Lyman-$\alpha$ lines and the FeII and MgII resonance lines along the line of sight toward the nearby (12.5 pc) star Capella. These observations were obtained at orbital phase 0.80 when the combined stellar emission lines had different shapes compared to those obtained in earlier observations at phase 0.26 and analyzed by Linsky et al. (ApJ 402, 694 (1993)). By reversing the radial velocities of the two stars we are better able to derive the intrinsic stellar profiles, especially for the Lyman $\alpha$ line, and therefore to determine the interstellar absorption lines more precisely.
We compare the derived properties of the local interstellar medium (D/H ratio, temperature, turbulent velocity, hydrogen column density, and gas phase abundances) for Capella at the two phases with the properties derived for the line of sight to another nearby (3.5 pc) star Procyon.
This work is supported by NASA grant S-56460-D to the National Institute of Standards and Technology.
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