X-Ray Coronal Properties of Swift/BAT-selected Seyfert 1 Active Galactic Nuclei

Kamraj N, Brightman M, Harrison FA, Stern D, Garcia JA, Balokovic M, Ricci C, Koss MJ, Mejia-Restrepo JE, Oh K, Powell MC, Urry CM (2022)

Publication Type: Journal article

Publication year: 2022


Book Volume: 927

Journal Issue: 1

DOI: 10.3847/1538-4357/ac45f6


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, Gamma, and Eddington ratio. This calls into question the use of such relations to infer properties of supermassive black hole systems.

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How to cite


Kamraj, N., Brightman, M., Harrison, F.A., Stern, D., Garcia, J.A., Balokovic, M.,... Urry, C.M. (2022). X-Ray Coronal Properties of Swift/BAT-selected Seyfert 1 Active Galactic Nuclei. Astrophysical Journal, 927(1). https://doi.org/10.3847/1538-4357/ac45f6


Kamraj, Nikita, et al. "X-Ray Coronal Properties of Swift/BAT-selected Seyfert 1 Active Galactic Nuclei." Astrophysical Journal 927.1 (2022).

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