UV spectral diagnostics for low redshift quasars: estimating physical conditions and radius of the Broad Line Region

Abstract

The UV spectral range (1100 - 3000 A) contains the strongest resonance lines observed in active galactic nuclei (AGN). Analysis of UV line intensity ratios and profile shapes in quasar spectra provide diagnostics of physical and dynamical conditions in the broad line emitting region. This paper discusses properties of UV lines in type-1 AGN spectra, and how they lead an estimate of ionizing photon flux, chemical abundances, radius of the broad line emitting region and central black hole mass. These estimates are meaningfully contextualised through the 4D "eigenvector-1" (4DE1) formalism.

arXiv commentContributed paper presented at the ESO/NUVA/IAG Workshop on Challenges in UV Astronomy ESO, Garching, 7-11 October 2013. Accepted for publication in Astrophysics and Space Science

References in corpus (44)

• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• Composite Quasar Spectra From the Sloan Digital Sky Survey
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
• The Low-Luminosity End of the Radius-Luminosity Relationship for Active Galactic Nuclei
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei: I. Comparing the Photoionization and Reverberation Techniques
• An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zw 1
• The Canada-France High-z Quasar Survey: nine new quasars and the luminosity function at redshift 6
• Black Hole Mass and Eddington Ratio as Drivers for the Observable Properties of Radio-Loud and Radio-Quiet QSOs
• Systematic Effects in Measurement of Black Hole Masses by Emission-Line Reverberation of Active Galactic Nuclei: Eddington Ratio and Inclination
• The 2013 Release of Cloudy
• Unification of Luminous Type 1 Quasars through CIV Emission
• The diversity of quasars unified by accretion and orientation
• Keplerian Motion of Broad-Line Region Gas as Evidence for Supermassive Black Holes in Active Galactic Nuclei
• Comparing Single-Epoch Virial Black Hole Mass Estimators for Luminous Quasars
• Black Hole Growth to z = 2 - I: Improved Virial Methods for Measuring M_BH and L/L_Edd
• CIV 1549 as an Eigenvector 1 Parameter for Active Galactic Nuclei
• The Structure of the Broad Line Region in AGN: I. Reconstructed Velocity-Delay Maps
• Searching for the Physical Drivers of the Eigenvector 1 Correlation Space
• Black-Hole Mass and Growth Rate at High Redshift
• "Comets" orbiting a black hole
• Gas Metallicity in the Narrow-Line Regions of High-Redshift Active Galactic Nuclei
• Average Quasar Spectra in the Context of Eigenvector 1
• The metallicity of the most distant quasars
• Detailed Characterization of H_beta emission line profile in low z SDSS quasars
• Average UV Quasar Spectra in the Context of Eigenvector 1: A Baldwin Effect Governed by Eddington Ratio?
• Predicted FeII Emission-Line Strengths from Active Galactic Nuclei
• Implications of infalling Fe II - emitting clouds in active galactic nuclei: anisotropic properties
• Is Mg II 2800 a Reliable Virial Broadening Estimator for Quasars?
• BLR Physical Conditions in Extreme Population A Quasars: a Method to Estimate Central Black Hole Mass at High Redshift
• The Civ line width distribution for quasars and its implications for broad-line region dynamics and virial mass estimation
• The Demise of the Classical BLR in the Luminous Quasar PG1416-129
• The mass-metallicity relation of SDSS quasars
• Close supermassive binary black holes
• The chemical properties of low-redshift QSOs
• Reverberation and photoionization estimates of the Broad Line Region Radius in Low-z Quasars
• PCA of the spectral energy distribution and emission line properties of red 2MASS AGN
• Two-Component Structure of the Hbeta Broad-Line Region in Quasars. I. Evidence from Spectral Principal Component Analysis
• The Optical and Ultraviolet Emission-Line Properties of Bright Quasars with Detailed Spectral Energy Distributions
• CIV Emission and the Ultraviolet through X-ray Spectral Energy Distribution of Radio-Quiet Quasars
• The Redshifted Excess in Quasar C IV Broad Emission Lines
• Implications from the optical to UV flux ratio of FeII emission in quasars
• Optical emission line properties of a sample of the broad-line AGNs: the Baldwin effect and eigenvector 1
• Fifty Years of Quasars: Physical Insights and Potential for Cosmology
• Quasars with Anomalous Hβ Profiles I: Demographics

Cited by in corpus (6)

• BASS XXV: DR2 Broad-line Based Black Hole Mass Estimates and Biases from Obscuration
• The Evolution of Chemical Abundance in Quasar Broad Line Region
• The CaFe Project: Optical Fe II and Near-Infrared Ca II triplet emission in active galaxies -- simulated EWs, the co-dependence of cloud sizes and metal content
• The most powerful quasar outflows as revealed by the Civ λ1549 resonance line
• The CaFe Project: Optical Fe II and Near-Infrared Ca II triplet emission in active galaxies: (I) Photoionization modelling
• The physical driver of the optical Eigenvector 1 in Quasar Main Sequence