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Interstellar Deuterium, Nitrogen, and Oxygen Abundances Toward GD 246, WD 2331$-$475, HZ 21, and Lan 23: Results from the FUSE Mission

Cristina M. Oliveira·Guillaume Hebrard·J. Christopher Howk·Jeffrey W. Kruk·Pierre Chayer·H. Warren Moos
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Abstract

The interstellar abundances of D I, N I, and O I in the local ISM are studied us ing high-resolution spectra of four hot white dwarfs. The spectra of GD 246, WD 2331$-$475, HZ 21, and Lan 23 were obtained with the {\it Far Ultraviolet Spectroscopic Explorer} FUSE in the wavelength range 905-1187 A. The line of sight to GD 246 probes the Local Interstellar Cloud and at least one other H I cloud inside the Local Bubble, which contains most of the gas seen al ong this line of sight. The column densities of H I, C II*, S II, and Si II are measured using archival STIS echelle-mode observations. The H I column density is determined by fitting the strong damping wings of inte rstellar Lyman alpha using a model atmosphere to account for the stellar continuum. We combine the different abundance ratios computed here with previous published values to produce revised FUSE abundance ratios for DI/HI, OI/HI, NI/HI, DI/NI, DI/OI, and OI/NI.

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Cristina M. Oliveira, Guillaume Hebrard, J. Christopher Howk, Jeffrey W. Kruk, Pierre Chayer, H. Warren Moos. 2002-12-23. Interstellar Deuterium, Nitrogen, and Oxygen Abundances Toward GD 246, WD 2331$-$475, HZ 21, and Lan 23: Results from the FUSE Mission. https://doi.org/10.1086/368019

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