2002ApJS..140...19K

We present an analysis of interstellar absorption along the line of sight to the nearby white dwarf star HZ 43A. The distance to this star is 68±13 pc, and the line of sight extends toward the north Galactic pole. Column densities of O I, N I, and N II were derived from spectra obtained by the Far Ultraviolet Spectroscopic Explorer (FUSE), the column density of D I was derived from a combination of our FUSE spectra and an archival Hubble Space Telescope (HST) GHRS spectrum, and the column density of H I was derived from a combination of the GHRS spectrum and values derived from Extreme Ultraviolet Explorer (EUVE) data obtained from the literature. We find the following abundance ratios (with 2 σ uncertainties): DI/HI=(1.66±0.28)x10^–5, OI/HI=(3.63±0.84)x10^–4, and NI/HI=(3.80±0.74)x10^–5. The N II column density was slightly greater than that of N I, indicating that ionization corrections are important when deriving nitrogen abundances. Other interstellar species detected along the line of sight were C II, C III, O VI, Si II, Ar I, Mg II, and Fe II; an upper limit was determined for N III. No elements other than H I were detected in the stellar photosphere.