Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/30729
Title: | Compton-thick AGNs in the NuSTAR Era. III. A Systematic Study of the Torus Covering Factor | Authors: | MARCHESI, STEFANO Ajello, M. Zhao, X. Marcotulli, L. Baloković, M. Brightman, M. COMASTRI, Andrea CUSUMANO, GIANCARLO LANZUISI, Giorgio LA PAROLA, VALENTINA SEGRETO, ALBERTO Vignali, C. |
Issue Date: | 2019 | Journal: | THE ASTROPHYSICAL JOURNAL | Number: | 872 | Issue: | 1 | First Page: | 8 | Abstract: | We present the analysis of a sample of 35 candidate Compton-thick active galactic nuclei (AGNs) selected in the nearby universe (average redshift < z> ∼ 0.03) with the Swift-BAT 100-month survey. All sources have available NuSTAR data, thus allowing us to constrain with unprecedented quality important spectral parameters such as the obscuring torus line-of-sight column density (N_H,z), the average torus column density (N_H,tor), and the torus covering factor (f_c ). We compare the best-fit results obtained with the widely used MYTorus (Murphy & Yaqoob 2009) model with those of the recently published borus02 model (Baloković et al. 2018) used in the same geometrical configuration of MYTorus (i.e., with f_c = 0.5). We find a remarkable agreement between the two, although with increasing dispersion in N_H,z moving toward higher column densities. We then use borus02 to measure f_c . High-f_c sources have, on average, smaller offset between N_H,z and N_H,tor than low-f_c ones. Therefore, low f_c values can be linked to a “patchy torus” scenario, where the AGN is seen through an overdense region in the torus, while high-f_c objects are more likely to be obscured by a more uniform gas distribution. Finally, we find potential evidence of an inverse trend between f_c and the AGN 2-10 keV luminosity, i.e., sources with higher f_c values have on average lower luminosities. | URI: | http://hdl.handle.net/20.500.12386/30729 | URL: | https://iopscience.iop.org/article/10.3847/1538-4357/aafbeb | ISSN: | 0004-637X | DOI: | 10.3847/1538-4357/aafbeb | Bibcode ADS: | 2019ApJ...872....8M | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
Marchesi_2019_ApJ_872_8.pdf | Pdf editoriale | 1.06 MB | Adobe PDF | View/Open |
Page view(s)
42
checked on Mar 29, 2024
Download(s)
13
checked on Mar 29, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.