Using simultaneous modeling of continuum lag-spectrum and broadband SED of Fairall 9 with the H0RIZON-AGN model, the authors obtain H0 = 72.4_{-3.7}^{+3.4} km s^{-1} Mpc^{-1}.
What controls the Fe II strength in active galactic nuclei?
2 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
We used a large, homogeneous sample of 4178 z <= 0.8 Seyfert 1 galaxies and QSOs selected from the Sloan Digital Sky Survey to investigate the strength of Fe II emission and its correlation with other emission lines and physical parameters of active galactic nuclei. We find that the strongest correlations of almost all the emission-line intensity ratios and equivalent widths (EWs) are with the Eddington ratio (L/L_{Edd}), rather than with the continuum luminosity at 5100\AA\ (L_{5100}) or black hole mass (M_{BH}); the only exception is the EW of ultraviolet Fe II emission, which does not correlate at all with broad-line width, L_{5100}, M_{BH}, or L/L_{Edd}. By contrast, the intensity ratios of both the ultraviolet and optical Fe II emission to Mg II \lambda 2800 correlate quite strongly with L/L_{Edd}. Interestingly, among all the emission lines in the near-UV and optical, the EW of narrow optical Fe II emission has the strongest correlation with L/L_{Edd}. We suggest that the variation of the emission-line strength in active galaxies is regulated by L/L_{Edd} because it governs the global distribution of the column density of the clouds gravitationally bound in the line-emitting region, as well as its overall gas supply. The systematic dependence on L/L_{Edd} must be corrected when using the FeII/MgII intensity ratio as a measure of the Fe/Mg abundance ratio to study the history of chemical evolution in QSO environments.
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astro-ph.GA 2years
2026 2verdicts
UNVERDICTED 2representative citing papers
JWST spectra reveal that two z~7 galaxies already show near-solar iron-to-silicon ratios with no strong odd-even effect, favoring early Type Ia supernovae over pair-instability supernovae as the source of iron enrichment.
citing papers explorer
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HALO II: Constraining Hubble constant $H_{0}$ through continuum delay fitting of Fairall 9
Using simultaneous modeling of continuum lag-spectrum and broadband SED of Fairall 9 with the H0RIZON-AGN model, the authors obtain H0 = 72.4_{-3.7}^{+3.4} km s^{-1} Mpc^{-1}.
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JWST Absorption-Line Analysis of UV-Bright Galaxies at $z=7.2-10.6$: Early Chemical Enrichment Traced by C, O, Mg, Al, Si, and Fe
JWST spectra reveal that two z~7 galaxies already show near-solar iron-to-silicon ratios with no strong odd-even effect, favoring early Type Ia supernovae over pair-instability supernovae as the source of iron enrichment.