Quasar main sequence in the UV plane

Abstract

Active galaxies form a clear pattern in the optical plane showing the correlation between the Full Width Half Maximum (FWHM) of the H$\beta$ line and the ratio of the Equivalent Width (EW) of the optical FeII emission and the EW(H$\beta$). This pattern is frequently refereed to as the quasar main sequence. In this paper we study the UV plane showing FWHM of the MgII line against the ratio of EW of UV FeII emission to EW(MgII). We show that the UV plane trends are different, with the underlying strong correlation between FWHM(MgII) and EW(MgII). This correlation is entirely driven by the choice of the continuum used to measure EW(MgII). If we correct for the strong curvature in the UV continuum related to the character of emission expected from accretion disk, the behavior of the FWHM vs. EW for MgII becomes similar to the behaviour of H$\beta$. Such a similarity is expected since both lines belong to the Low Ionization group of emission lines and come from a similar region. Such a similarity and weak coupling between FWHM and EW of the corresponding line is then also consistent with the Broad Line Region model based on the presence of dust in the accretion disk atmosphere.

arXiv comment15 pages, 11 figures

References in corpus (38)

• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
• A Catalog of Quasar Properties from SDSS DR7
• The Low-Luminosity End of the Radius-Luminosity Relationship for Active Galactic Nuclei
• Active Galactic Nuclei: what's in a name?
• An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zw 1
• The diversity of quasars unified by accretion and orientation
• Eigenvector 1: An Optimal Correlation Space for Active Galactic Nuclei
• The unusual emission line spectrum of IZw1
• The origin of the Broad Line Region in Active Galactic Nuclei
• The New Generation Atlas of Quasar Spectral Energy Distributions from Radio to X-rays
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H$\beta$ Time Lags and Implications for Super-Eddington Accretion
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IX 10 New Observations of Reverberation Mapping and Shortened H$\beta$ Lags
• Average Quasar Spectra in the Context of Eigenvector 1
• Detailed Characterization of H_beta emission line profile in low z SDSS quasars
• The effect of nuclear gas distribution on the mass determination of supermassive black holes
• New Insights on the QSO Radio-Loud/Radio-Quiet Dichotomy: SDSS Spectra in the Context of the 4D Eigenvector1 Parameter Space
• The Quasar Main Sequence explained by the combination of Eddington ratio, metallicity and orientation
• Modelling of the quasar main sequence in the optical plane
• Predicting Quasar Continua Near Lyman-$\alpha$ with Principal Component Analysis
• Failed radiatively Accelerated Dusty Outflow model of the Broad Line Region in Active Galactic Nuclei. I. Analytical solution
• QSFit: Automatic analysis of optical AGN spectra
• Two-phase radiative/conductive equilibrium in AGN and GBH
• The UV and optical Fe II emission lines in type 1 AGNs
• The Relationship Between the High Energy Continuum and Emission Lines in QSOs: A Low-Redshift Sample
• The dust origin of the Broad Line Region and the model consequences for AGN unification scheme
• CLOUDY view of the warm corona
• PCA of the spectral energy distribution and emission line properties of red 2MASS AGN
• The intermediate line region in active galactic nuclei
• Optical and X-ray properties of the RIXOS AGN: II - Emission lines
• Intermediate-line Emission in AGNs: The Effect of Prescription of the Gas Density
• Relation between the variations in the MgII $\lambda 2798$ emission-line and the 3000 Å continuum
• Multi-phase environment of compact galactic nuclei: the role of the Nuclear Star Cluster
• Main trends of the quasar main sequence -- effect of viewing angle
• The physical driver of the optical Eigenvector 1 in Quasar Main Sequence
• Thermal instability in X-ray photoionized media in Active Galactic Nuclei: II. Role of the thermal conduction in warm absorber
• SALT long-slit spectroscopy of HE 0435-4312: fast displacement in the Mg II emission line
• How Similar are the Properties of Quasars with Nearly Identical Ultraviolet Spectra?

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• Consistency study of high- and low-accreting Mg ii quasars: No significant effect of the Fe ii to Mg ii flux ratio on the radius-luminosity relation dispersion
• High-redshift quasars along the Main Sequence
• The intermediate-ionization lines as virial broadening estimators for Population A quasars
• Statistical analysis of AlIII 1860 and CIII] 1909 emission lines as virial black hole mass estimators in quasars
• UV Fe II emission model of HE 0413-4031 and its relation to broad-line time delays
• Far-UV Fe Emission as Proxy of Eddington Ratios