Published September 2019 | Version Submitted + Published
Journal Article Open

X-ray spectral and eclipsing model of the clumpy obscurer in active galactic nuclei

  • 1. ROR icon Pontificia Universidad Católica de Chile
  • 2. ROR icon Excellence Cluster Universe
  • 3. ROR icon California Institute of Technology
  • 4. ROR icon Max Planck Institute for Extraterrestrial Physics
  • 5. ROR icon NOIRLab
  • 6. ROR icon Millennium Institute of Astrophysics
  • 7. ROR icon Space Science Institute

Abstract

We present a unification model for a clumpy obscurer in active galactic nuclei (AGN) and investigate the properties of the resulting X-ray spectrum. Our model is constructed to reproduce the column density distribution of the AGN population and cloud eclipse events in terms of their angular sizes and frequency. We developed and released a generalised Monte Carlo X-ray radiative transfer code, XARS, to compute X-ray spectra of obscurer models. The geometry results in strong Compton scattering, causing soft photons to escape also along Compton-thick sight lines. This makes our model spectra very similar to our TORUS previous model. However, only if we introduce an additional Compton-thick reflector near the corona, we achieve good fits to NuSTAR spectra. This additional component in our model can be interpreted as part of the dust-free broad-line region, an inner wall or rim, or a warped disk. It cannot be attributed to a simple disk because the reflector must simultaneously block the line of sight to the corona and reflect its radiation. We release our model as an Xspec table model and present corresponding CLUMPY infrared spectra, paving the way for self-consistent multi-wavelength analyses.

Additional Information

© 2019 ESO. Article published by EDP Sciences. Received 3 December 2018; Accepted 18 July 2019; Published online 27 August 2019. We thank the anonymous referee for careful reading of the manuscript and their insightful comments. JB thanks Marc Schartmann and Leonard Burtscher for discussions on tori in the infrared. JB thanks Eva Lefa for sharing her Monte Carlo code to verify our Compton scattering implementation. JB thanks Mislav Baloković for insightful conversations. We acknowledge support from the CONICYT-Chile grants Basal-CATA PFB-06/2007 & AFB-170002 (JB, FEB), FONDECYT Regular 1141218 (FEB), FONDECYT Postdoctorados 3160439 (JB) and the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS (JB, FEB). This research was supported by the DFG cluster of excellence "Origin and Structure of the Universe".

Attached Files

Published - aa34771-18.pdf

Submitted - 1907.13137.pdf

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1907.13137.pdf

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Additional details

Identifiers

Eprint ID
97734
Resolver ID
CaltechAUTHORS:20190809-153450175

Funding

Basal-CATA
PFB-06/2007
Basal-CATA
AFB-170002
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT)
1141218
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT)
3160439
Iniciativa Científica Milenio del Ministerio de Economía, Fomento y Turismo
IC120009
Deutsche Forschungsgemeinschaft (DFG)

Dates

Created
2019-08-09
Created from EPrint's datestamp field
Updated
2023-06-01
Created from EPrint's last_modified field

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