Ultraviolet Lines and Gas Composition in NGC 1068
نویسنده
چکیده
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 O iii]λ1663 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.
منابع مشابه
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تاریخ انتشار 2008