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arXiv · 1608.02847

High-energy monitoring of NGC 4593 with XMM-Newton and NuSTAR. X-ray spectral analysis

F. Ursini·P. -O. Petrucci·G. Matt·S. Bianchi·M. Cappi·B. De Marco·A. De Rosa·J. Malzac·A. Marinucci·G. Ponti·A. Tortosa
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Abstract

We present results from a joint Xmm-Newton/NuSTAR monitoring of the Seyfert 1 NGC 4593, consisting of 5x20 ks simultaneous observations spaced by two days, performed in January 2015. The source is variable, both in flux and spectral shape, on time-scales down to a few ks and with a clear softer-when-brighter behaviour. In agreement with past observations, we find the presence of a warm absorber well described by a two-phase ionized outflow. The source exhibits a cold, narrow and constant Fe K alpha line at 6.4 keV, and a broad component is also detected. The broad-band (0.3-79 keV) spectrum is well described by a primary power law with Gamma=1.6-1.8 and an exponential cut-off varying from 90(+40,-20) keV to >700 keV, two distinct reflection components, and a variable soft excess correlated with the primary power law. This campaign shows that probing the variability of Seyfert 1 galaxies on different time-scales is of prime importance to investigate the high-energy emission of AGNs.

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F. Ursini, P. -O. Petrucci, G. Matt, S. Bianchi, M. Cappi, B. De Marco, A. De Rosa, J. Malzac, A. Marinucci, G. Ponti, A. Tortosa. 2016-08-09. High-energy monitoring of NGC 4593 with XMM-Newton and NuSTAR. X-ray spectral analysis. https://doi.org/10.1093/mnras%2Fstw2022

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