SOFIA observations of the planetary nebula NGC 7009
نویسندگان
چکیده
منابع مشابه
On the nitrogen abundance of FLIERs : the outer knots of the planetary nebula NGC 7009
We have constructed a 3D photoionisation model of a planetary nebula (PN) similar in structure to NGC 7009 with its outer pair of knots (also known as FLIERs –fast, low-ionization emission regions). The work is motivated by the fact that the strong [N ii]λ6583 line emission from FLIERs in many planetary nebulae has been attributed to a significant local overabundance of nitrogen. We explore the...
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ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2011
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s174392131201071x