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Title: X-Ray Coronal Properties of Swift/BAT-selected Seyfert 1 Active Galactic Nuclei
The corona is an integral component of active galactic nuclei (AGNs) which produces the bulk of the X-ray emission above 1-2 keV. However, many of its physical properties and the mechanisms powering this emission remain a mystery. In particular, the temperature of the coronal plasma has been difficult to constrain for large samples of AGNs, as constraints require high-quality broadband X-ray spectral coverage extending above 10 keV in order to measure the high-energy cutoff, which provides constraints on the combination of coronal optical depth and temperature. We present constraints on the coronal temperature for a large sample of Seyfert 1 AGNs selected from the Swift/BAT survey using high-quality hard X-ray data from the NuSTAR observatory combined with simultaneous soft X-ray data from Swift/XRT or XMM-Newton. When applying a physically motivated, nonrelativistic disk-reflection model to the X-ray spectra, we find a mean coronal temperature kT e = 84 ± 9 keV. We find no significant correlation between the coronal cutoff energy and accretion parameters such as the Eddington ratio and black hole mass. We also do not find a statistically significant correlation between the X-ray photon index, Γ, and Eddington ratio. This calls into question the use of such relations to infer properties of supermassive black hole systems.  more » « less
Award ID(s):
1715512
PAR ID:
10339300
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
The astrophysical journal
Volume:
927
ISSN:
1538-4357
Page Range / eLocation ID:
42
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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