LYMAN-ALPHA ABSORPTION AND THE D H RATIO IN THE LOCAL INTERSTELLAR-MEDIUM/

Using the Goddard High Resolution Spectrograph onboard the Hubble Spac e Telescope, we have observed Ly alpha absorption against stellar chro mospheres along six lines of sight, with additional observations of th e Mg II H and K lines along five of the lines of sight and Fe II absor ption along four of the lines of sight. We found absorption near the p rojected velocity of the local interstellar cloud (LIC) along three li nes of sight. The velocity toward the stars beta Gem and sigma Gem was only marginally consistent with the LIC. The single interstellar comp onent toward 31 Com had a velocity that was inconsistent with the proj ected LIC velocity. Three of the lines of sight showed a multicomponen t velocity structure. For the star epsilon Eri we required an addition al hot, low-density component which we have interpreted as a stellar h ydrogen wall. The LIC temperatures derived from our data range from 78 00 to 9700 K with values of the microturbulence parameter less than 2. 0 km s(-1). The measured D/H ratio for the LIC along every sight line is consistent with a value of 1.6 x 10(-5), the best determined value being the beta Cas line of sight with D/H = 1.7 +/- 0.3 x 10(-5).