Anatomy of the AGN in NGC 5548: III. The high-energy view with NuSTAR and INTEGRAL

F. Ursini; R. Boissay; P. -O. Petrucci; G. Matt; M. Cappi; S. Bianchi; J. Kaastra; F. Harrison; D. J. Walton; L. di Gesu; E. Costantini; B. De Marco; G. A. Kriss; M. Mehdipour; S. Paltani; B. M. Peterson; G. Ponti; K. C. Steenbrugge

doi:10.1051/0004-6361/201425401

arXiv · 1501.03426

Anatomy of the AGN in NGC 5548: III. The high-energy view with NuSTAR and INTEGRAL

F. Ursini·R. Boissay·P. -O. Petrucci·G. Matt·M. Cappi·S. Bianchi·J. Kaastra·F. Harrison·D. J. Walton·L. di Gesu·E. Costantini·B. De Marco·G. A. Kriss·M. Mehdipour·S. Paltani·B. M. Peterson·G. Ponti·K. C. Steenbrugge

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Abstract

We describe the analysis of the seven broad-band X-ray continuum observations of the archetypal Seyfert 1 galaxy NGC 5548 that were obtained with XMM-Newton or Chandra, simultaneously with high-energy (> 10 keV) observations with NuSTAR and INTEGRAL. These data were obtained as part of a multiwavelength campaign undertaken from the summer of 2013 till early 2014. We find evidence of a high-energy cut-off in at least one observation, which we attribute to thermal Comptonization, and a constant reflected component that is likely due to neutral material at least a few light months away from the continuum source. We confirm the presence of strong, partial covering X-ray absorption as the explanation for the sharp decrease in flux through the soft X-ray band. The obscurers appear to be variable in column density and covering fraction on time scales as short as weeks. A fit of the average spectrum over the range 0.3-400 keV with a realistic Comptonization model indicates the presence of a hot corona with a temperature of 40(+40,-10) keV and an optical depth of 2.7(+0.7,-1.2) if a spherical geometry is assumed.

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F. Ursini, R. Boissay, P. -O. Petrucci, G. Matt, M. Cappi, S. Bianchi, J. Kaastra, F. Harrison, D. J. Walton, L. di Gesu, E. Costantini, B. De Marco, G. A. Kriss, M. Mehdipour, S. Paltani, B. M. Peterson, G. Ponti, K. C. Steenbrugge. 2015-01-14. Anatomy of the AGN in NGC 5548: III. The high-energy view with NuSTAR and INTEGRAL. https://doi.org/10.1051/0004-6361%2F201425401

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