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Title: Exploring the diversity of Type 1 active galactic nuclei identified in SDSS-IV/SPIDERS

Abstract

ABSTRACT We present a statistical analysis of the optical properties of an X-ray-selected Type 1 active galactic nucleus (AGN) sample, using high signal-to-noise ratio (S/N>20) spectra of the counterparts of the ROSAT/2RXS sources in the footprint of the SDSS-IV/SPIDERS (Spectroscopic IDentification of eROSITA Sources) programme. The final sample contains 2100 sources. It significantly extends the redshift and luminosity ranges (z ∼ 0.01–0.80 and $$L_{\rm 0.1\!-\!2.4 \, keV} \sim \rm 2.0 \times 10^{41}\!-\!1.0 \times 10^{46} \, \, erg \, s^{-1}$$) used so far in this kind of analysis. By means of a principal component analysis, we derive eigenvector (EV) 1 and 2 in an eleven-dimensional optical and X-ray parameter space, which are consistent with previous results. The validity of the correlations of the Eddington ratio L/LEdd with EV1 and the black hole mass with EV2 is strongly confirmed. These results imply that L/LEdd and black hole mass are related to the diversity of the optical properties of Type 1 AGNs. Investigating the relation of the width and asymmetry of H β and the relative strength of the iron emission $$r_{\rm Fe\, \small{II}}$$, we show that our analysis supports the presence of a distinct kinematic region: the very broad line region. Furthermore, comparing sources with a red-asymmetric broad H β emission line to sources for which it is blue asymmetric, we find an intriguing difference in the correlation of the $$\rm Fe\, \small{II}$$ and the continuum emission strengths. We show that this contrasting behaviour is consistent with a flattened, stratified model of the broad-line region, in which the $$\rm Fe\, \small{II}$$-emitting region is shielded from the central source.

Authors:
 [1]; ORCiD logo [1];  [1];  [1];  [1];  [1];  [2];  [3];  [1];  [4];  [1]
  1. Max-Planck-Institut für extraterrestrische Physik, Gießenbachstraße 1, D-85748 Garching, Germany
  2. School of Physics and Astronomy, Tel-Aviv University, Tel Aviv 69978, Israel
  3. Instituto de Física de Cantabria (CSIC-Universidad de Cantabria), E-39005 Santander, Spain
  4. Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA, Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1595149
Resource Type:
Published Article
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Name: Monthly Notices of the Royal Astronomical Society Journal Volume: 492 Journal Issue: 3; Journal ID: ISSN 0035-8711
Publisher:
Oxford University Press
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Wolf, Julien, Salvato, Mara, Coffey, Damien, Merloni, Andrea, Buchner, Johannes, Arcodia, Riccardo, Baron, Dalya, Carrera, Francisco J., Comparat, Johan, Schneider, Donald P., and Nandra, Kirpal. Exploring the diversity of Type 1 active galactic nuclei identified in SDSS-IV/SPIDERS. United Kingdom: N. p., 2020. Web. doi:10.1093/mnras/staa018.
Wolf, Julien, Salvato, Mara, Coffey, Damien, Merloni, Andrea, Buchner, Johannes, Arcodia, Riccardo, Baron, Dalya, Carrera, Francisco J., Comparat, Johan, Schneider, Donald P., & Nandra, Kirpal. Exploring the diversity of Type 1 active galactic nuclei identified in SDSS-IV/SPIDERS. United Kingdom. doi:10.1093/mnras/staa018.
Wolf, Julien, Salvato, Mara, Coffey, Damien, Merloni, Andrea, Buchner, Johannes, Arcodia, Riccardo, Baron, Dalya, Carrera, Francisco J., Comparat, Johan, Schneider, Donald P., and Nandra, Kirpal. Wed . "Exploring the diversity of Type 1 active galactic nuclei identified in SDSS-IV/SPIDERS". United Kingdom. doi:10.1093/mnras/staa018.
@article{osti_1595149,
title = {Exploring the diversity of Type 1 active galactic nuclei identified in SDSS-IV/SPIDERS},
author = {Wolf, Julien and Salvato, Mara and Coffey, Damien and Merloni, Andrea and Buchner, Johannes and Arcodia, Riccardo and Baron, Dalya and Carrera, Francisco J. and Comparat, Johan and Schneider, Donald P. and Nandra, Kirpal},
abstractNote = {ABSTRACT We present a statistical analysis of the optical properties of an X-ray-selected Type 1 active galactic nucleus (AGN) sample, using high signal-to-noise ratio (S/N>20) spectra of the counterparts of the ROSAT/2RXS sources in the footprint of the SDSS-IV/SPIDERS (Spectroscopic IDentification of eROSITA Sources) programme. The final sample contains 2100 sources. It significantly extends the redshift and luminosity ranges (z ∼ 0.01–0.80 and $L_{\rm 0.1\!-\!2.4 \, keV} \sim \rm 2.0 \times 10^{41}\!-\!1.0 \times 10^{46} \, \, erg \, s^{-1}$) used so far in this kind of analysis. By means of a principal component analysis, we derive eigenvector (EV) 1 and 2 in an eleven-dimensional optical and X-ray parameter space, which are consistent with previous results. The validity of the correlations of the Eddington ratio L/LEdd with EV1 and the black hole mass with EV2 is strongly confirmed. These results imply that L/LEdd and black hole mass are related to the diversity of the optical properties of Type 1 AGNs. Investigating the relation of the width and asymmetry of H β and the relative strength of the iron emission $r_{\rm Fe\, \small{II}}$, we show that our analysis supports the presence of a distinct kinematic region: the very broad line region. Furthermore, comparing sources with a red-asymmetric broad H β emission line to sources for which it is blue asymmetric, we find an intriguing difference in the correlation of the $\rm Fe\, \small{II}$ and the continuum emission strengths. We show that this contrasting behaviour is consistent with a flattened, stratified model of the broad-line region, in which the $\rm Fe\, \small{II}$-emitting region is shielded from the central source.},
doi = {10.1093/mnras/staa018},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 3,
volume = 492,
place = {United Kingdom},
year = {2020},
month = {1}
}

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DOI: 10.1093/mnras/staa018

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The Baldwin Effect and Black Hole Accretion: A Spectral Principal Component Analysis of a Complete Quasar Sample
journal, March 2003

  • Shang, Zhaohui; Wills, Beverley J.; Robinson, Edward L.
  • The Astrophysical Journal, Vol. 586, Issue 1
  • DOI: 10.1086/367638

AGN Host Galaxies at z  ~ 0.4-1.3: Bulge-dominated and Lacking Merger-AGN Connection
journal, June 2005

  • Grogin, N. A.; Conselice, C. J.; Chatzichristou, E.
  • The Astrophysical Journal, Vol. 627, Issue 2
  • DOI: 10.1086/432256

Long-Term Profile Variability in Active Galactic Nucleus with Double-Peaked Balmer Emission Lines
journal, March 2010

  • Lewis, Karen T.; Eracleous, Michael; Storchi-Bergmann, Thaisa
  • The Astrophysical Journal Supplement Series, Vol. 187, Issue 2
  • DOI: 10.1088/0067-0049/187/2/416

Finding counterparts for all-sky X-ray surveys with Nway: a Bayesian algorithm for cross-matching multiple catalogues
journal, October 2017

  • Salvato, M.; Buchner, J.; Budavári, T.
  • Monthly Notices of the Royal Astronomical Society, Vol. 473, Issue 4
  • DOI: 10.1093/mnras/stx2651

Dissecting the Quasar main Sequence: Insight from host Galaxy Properties
journal, April 2015


Balmer lines emission region in NGC 3516: Kinematical and physical properties
journal, July 2002


Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution
journal, September 2017