Variability of emission lines in quasar spectra
نویسندگان
چکیده
منابع مشابه
Metallicities and Abundance Ratios from Quasar Broad Emission Lines
The broad emission lines (BELs) of quasars and active galactic nuclei (AGNs) are important diagnostics of the relative abundances and overall metallicity in the gas. Here we present new theoretical predictions for several UV BELs. We focus specifically on the relative nitrogen abundance as a metallicity indicator, based on the expected secondary enrichment of nitrogen at metallicities Z & 0.2 Z...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1986
ISSN: 0074-1809
DOI: 10.1017/s0074180900152982