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arXiv · 1507.01775

The NuSTAR X-ray spectrum of the low-luminosity AGN in NGC 7213

F. Ursini·A. Marinucci·G. Matt·S. Bianchi·A. Tortosa·D. Stern·P. Arévalo·D. R. Ballantyne·F. E. Bauer·A. C. Fabian·F. A. Harrison·A. M. Lohfink·C. S. Reynolds·D. J. Walton
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Abstract

We present an analysis of the 3-79 keV NuSTAR spectrum of the low-luminosity active galactic nucleus NGC 7213. In agreement with past observations, we find a lower limit to the high-energy cut-off of Ec > 140 keV, no evidence for a Compton-reflected continuum, and the presence of an iron Kalpha complex, possibly produced in the broad-line region. From the application of the MYTorus model, we find that the line-emitting material is consistent with the absence of a significant Compton reflection if arising from a Compton-thin torus of gas with a column density of 5.0(+2.0,-1.6) cm^-2. We report variability of the equivalent width of the iron lines on the time-scale of years using archival observations from XMM-Newton, Chandra and Suzaku. This analysis suggests a possible contribution from dusty gas. A fit with a Comptonization model indicates the presence of a hot corona with a temperature kTe > 40 keV and an optical depth tau < 1, assuming a spherical geometry.

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F. Ursini, A. Marinucci, G. Matt, S. Bianchi, A. Tortosa, D. Stern, P. Arévalo, D. R. Ballantyne, F. E. Bauer, A. C. Fabian, F. A. Harrison, A. M. Lohfink, C. S. Reynolds, D. J. Walton. 2015-07-07. The NuSTAR X-ray spectrum of the low-luminosity AGN in NGC 7213. https://arxiv.org/abs/1507.01775

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