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We analyze the X‐ray properties of the Compton‐thick Seyfert 1.9 radio quiet AGN in NGC 1194 using INTEGRAL (ISGRI), XMM‐Newton (EPIC), Swift (BAT and XRT), and Suzaku (XIS) observations. There is a set of Fe‐K lines in the NGC 1194 spectrum with complex relativistic profiles that can be considered as a sign of either a warped Bardeen‐Petterson accretion disk or double black hole. We compare our results on NGC 1194 with two other megamaser warped disk candidates, NGC 1068 and NGC 4258, to trace out the other properties which can be typical for AGNs with warped accretion disks. To finally confirm or disprove the double black‐hole hypotheses, further observations of the iron lines and their evolution of their shape with time are necessary. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

We present the spectral analysis with the Nuclear Spectroscopic Telescope Array (NuSTAR) of four isolated galaxies with active galactic nuclei selected from the 2MIG catalogue: NGC 5347, ESO 438‐009, MCG‐02‐09‐040, and IGR J11366‐6002. We also used the Swift/Burst Alert Telescope (BAT) data up to ∼150 keV for MCG 02‐09‐040, ESO 438‐009, and IGR J11366‐6002 as well as the Swift/XRT data in 0.3–10 keV energy band for NGC 5347, ESO 438‐009, and IGR J11366‐6002. All the sources appear to have the reflected spectrum component with different reflection fractions in addition to the primary power‐law continuum. We found that power‐law indices for these sources lie between 1.6 and 1.8. The spectra of two sources, NGC 5347 and MCG‐02‐09‐040, show the Fe Kα emission line. For both of these sources, the Fe Kα lines have a significant value of EW ∼1 keV. The X‐ray spectrum of NGC 5347 is best fitted by a pure reflection model with Ecut ∼ 117 keV and without the presence of any additional primary power‐law component. We also found that the X‐ray spectrum of MCG‐02‐09‐040 shows the presence of heavy neutral obscuration of NH ∼ 1024 cm−2. However, this provides a non‐physical value of reflection in the case with fitting by a simple reflection model. A more appropriate fit is obtained with adopting the physical Monte Carlo‐based model as BNTorus. It allowed us to determine the absorption value of NH ∼ 1.04 × 1024 cm−2 and reasonable power‐law index of Γ ≈ 1.63. Results for MCG‐02‐09‐040 are presented for the first time.

The main idea of our research is to estimate the physical coalescence time of the double supermassive black hole (SMBH) system in the centre of NGC 6240 based on the X-ray observations from the Chandra space observatory. The spectra of the Northern and Southern nuclei were fitted by spectral models from Sherpa and both presented the narrow component of the Fe Kα emission line. It enabled us to apply the spectral model to these lines and to find relative offset ≈0.02 keV. The enclosed dynamical mass of the central region of NGC 6240 with radius 1 kpc was estimated $\approx 2.04\times 10^{11} \rm \,\, M_{\odot }$. These data allowed us to carry on the high resolution direct N-body simulations with Newtonian and post-Newtonian (up to $2.5\mathcal {PN}$ correction) dynamics for this particular double SMBH system. As a result, from our numerical models we approximated the central SMBH binary merging time for the different binary eccentricities. In our numerical parameters range the upper limit for the merging time, even for the very small eccentricities, is still below ≈70 Myr. Gravitational waveforms and amplitude-frequency pictures from such events can be detected using Pulsar Timing Array (PTA) projects at the last merging phase.

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We consider the sample of 55 blazars and Seyferts cross-correlated from the Planck all-sky survey based on the Early Release Compact Source Catalog (ERCSC) and Swift BAT 105-Month Hard X-ray Survey. The radio Planck spectra vs. X-ray Swift/XRT+BAT spectra of the active galactic nuclei (AGN) sample were fitted with the simple and broken power law (for the X-ray spectra taking into account also the Galactic neutral absorption) to test the dependencies between the photon indices of synchrotron emission (in radio range) and synchrotron self-Compton (SSC) or inverse-Compton emission (in X-rays). We show that for the major part of the AGN in our sample there is a correspondence between synchrotron and SSC photon indices (one of two for broken power-law model) compatible within the error levels. For such objects, this can give a good perspective for the task of distinguishing between the jet base counterpart from that one emitted in the disk-corona AGN “central engine”.