skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution

Abstract

The physical origin of the broad line region in active galactic nuclei is still unclear despite many years of observational studies. The reason is that the region is unresolved, and the reverberation mapping results imply a complex velocity field. We adopt a theory-motivated approach to identify the principal mechanism responsible for this complex phenomenon. We consider the possibility that the role of dust is essential. We assume that the local radiation pressure acting on the dust in the accretion disk atmosphere launches the outflow of material, but higher above the disk the irradiation from the central parts causes dust evaporation and a subsequent fallback. This failed radiatively accelerated dusty outflow is expected to represent the material forming low ionization lines. In this paper we formulate simple analytical equations to describe the cloud motion, including the evaporation phase. The model is fully described just by the basic parameters of black hole mass, accretion rate, black hole spin, and viewing angle. We study how the spectral line generic profiles correspond to this dynamic. We show that the virial factor calculated from our model strongly depends on the black hole mass in the case of enhanced dust opacity, and thus it then correlatesmore » with the line width. This could explain why the virial factor measured in galaxies with pseudobulges differs from that obtained from objects with classical bulges, although the trend predicted by the current version of the model is opposite to the observed trend.« less

Authors:
; ; ;  [1]; ;  [2]; ;  [3];  [4]
  1. Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland)
  2. Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China)
  3. Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw (Poland)
  4. Astronomical Institute, Academy of Sciences, Bocni II 1401, CZ-141 00 Prague (Czech Republic)
Publication Date:
OSTI Identifier:
22679854
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 846; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; ANALYTICAL SOLUTION; BLACK HOLES; COSMIC DUST; EQUATIONS; EVAPORATION; GALAXIES; GALAXY NUCLEI; IONIZATION; IRRADIATION; LINE WIDTHS; MASS; OPACITY; RADIATION PRESSURE

Citation Formats

Czerny, B., Panda, S., Wildy, C., Sniegowska, M., Li, Yan-Rong, Wang, J.-M., Hryniewicz, K., Sredzinska, J., and Karas, V., E-mail: bcz@cft.edu.pl. Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA8810.
Czerny, B., Panda, S., Wildy, C., Sniegowska, M., Li, Yan-Rong, Wang, J.-M., Hryniewicz, K., Sredzinska, J., & Karas, V., E-mail: bcz@cft.edu.pl. Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution. United States. doi:10.3847/1538-4357/AA8810.
Czerny, B., Panda, S., Wildy, C., Sniegowska, M., Li, Yan-Rong, Wang, J.-M., Hryniewicz, K., Sredzinska, J., and Karas, V., E-mail: bcz@cft.edu.pl. Sun . "Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution". United States. doi:10.3847/1538-4357/AA8810.
@article{osti_22679854,
title = {Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution},
author = {Czerny, B. and Panda, S. and Wildy, C. and Sniegowska, M. and Li, Yan-Rong and Wang, J.-M. and Hryniewicz, K. and Sredzinska, J. and Karas, V., E-mail: bcz@cft.edu.pl},
abstractNote = {The physical origin of the broad line region in active galactic nuclei is still unclear despite many years of observational studies. The reason is that the region is unresolved, and the reverberation mapping results imply a complex velocity field. We adopt a theory-motivated approach to identify the principal mechanism responsible for this complex phenomenon. We consider the possibility that the role of dust is essential. We assume that the local radiation pressure acting on the dust in the accretion disk atmosphere launches the outflow of material, but higher above the disk the irradiation from the central parts causes dust evaporation and a subsequent fallback. This failed radiatively accelerated dusty outflow is expected to represent the material forming low ionization lines. In this paper we formulate simple analytical equations to describe the cloud motion, including the evaporation phase. The model is fully described just by the basic parameters of black hole mass, accretion rate, black hole spin, and viewing angle. We study how the spectral line generic profiles correspond to this dynamic. We show that the virial factor calculated from our model strongly depends on the black hole mass in the case of enhanced dust opacity, and thus it then correlates with the line width. This could explain why the virial factor measured in galaxies with pseudobulges differs from that obtained from objects with classical bulges, although the trend predicted by the current version of the model is opposite to the observed trend.},
doi = {10.3847/1538-4357/AA8810},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 846,
place = {United States},
year = {2017},
month = {9}
}