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Ultraviolet Lines and Gas Composition in NGC 1068

Hagai Netzer
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Abstract

Recent ultraviolet and X-ray observations suggest that the Fe/O ratio in the NLR gas in NGC 1068 is abnormally high. The X-ray analysis, which is presented elsewhere, suggests a large Fe/H and the data shown and discussed here, in particular the extremely weak Oiii] 1664 line, argue for small O/N and O/C. Models to support this claim are shown and discussed. They include improved reddening estimates, dusty and dust-free calculations, and a range of abundances. The anomelous composition makes NGC 1068 unique among Seyfert galaxies and an unusual laboratory for investigating metal enrichment and depletion.

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Hagai Netzer. 1997-06-15. Ultraviolet Lines and Gas Composition in NGC 1068. https://doi.org/10.1023/a%3A1000509024526

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