Abundances in Spiral Galaxies: Evidence for Primary Nitrogen Production
نویسندگان
چکیده
منابع مشابه
Abundances in Spiral Galaxies: Evidence for Primary Nitrogen Production
We present the results of nitrogen and oxygen abundance measurements for 185 H II regions spanning a range of radius in 13 spiral galaxies. As expected, the nitrogen–to–oxygen ratio increases linearly with the oxygen abundance for high metallicity H II regions, indicating that nitrogen is predominately a secondary element. However, the nitrogen–to–oxygen ratio plateaus for oxygen abundances les...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1998
ISSN: 0004-637X
DOI: 10.1086/311263