FeII emission in NLS1s -- originating from denser regions with higher abundances?

Abstract

The interpretation of the main sequence of quasars has become a frontier subject in the last years. The consider the effect of a highly flattened, axially symmetric geometry for the broad-line region (BLR) on the parameters related to the distribution of quasars along their Main Sequence. We utilize the photoionization code CLOUDY to model the BLR, assuming `un-constant' virial factor with a strong dependence on the viewing angle. We show the preliminary results of the analysis to highlight the co-dependence of the Eigenvector 1 parameter, R${}_{\mathrm{FeII}}$ on the broad H$\beta$ FWHM (i.e. the line dispersion) and the inclination angle ($\theta$), assuming fixed values for the Eddington ratio (${\mathrm{L}}_{\mathrm{bol}}/{\mathrm{L}}_{\mathrm{Edd}}$), black hole mass (${\mathrm{M}}_{\mathrm{BH}}$) and spectral energy distribution (SED) shape. We consider four cases with changing cloud density (n${}_{\mathrm{H}}$) and composition. Understanding the FeII emitting region is crucial as this knowledge can be extended to the use of quasars as distance indicators for Cosmology.

arXiv comment5 pages, 2 figures, Proceedings of the IAU356: Nuclear Activity in Galaxies across Cosmic Time, Addis Ababa, Ethiopia (7-11 October, 2019)

References in corpus (7)

• Keplerian Motion of Broad-Line Region Gas as Evidence for Supermassive Black Holes in Active Galactic Nuclei
• Eigenvector 1: An Optimal Correlation Space for Active Galactic Nuclei
• An Atlas of Computed Equivalent Widths of Quasar Broad Emission Lines
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IX 10 New Observations of Reverberation Mapping and Shortened H$\beta$ Lags
• The Quasar Main Sequence explained by the combination of Eddington ratio, metallicity and orientation
• Modelling of the quasar main sequence in the optical plane
• Can reverberation-measured quasars be used for cosmology?