Some evidence of a double black hole in NGC 1194 active galactic nucleus?
1Vasylenko, AA, 2Fedorova, EV, 2Hnatyk, BI, 2Zhdanov, VI 1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine 2Astronomical Observatory of Taras Shevchenko National University of Kyiv, Kyiv, Ukraine |
Kinemat. fiz. nebesnyh tel (Online) 2015, 31(1):22-31 |
Start Page: Extragalactic Astronomy |
Language: Russian |
Abstract: On the basis of data from the XMM-Newton and INTEGRAL satellites, some properties of the X-ray emission from the active nucleus of the NGC 1194 galaxy are analyzed. Particular attention is paid to the energy region of X-ray spectrum between 6 and 7.5 keV, where, in addition to fluorescent iron lines FeKα (6.38 keV) and Fek (7.01 keV), we detected a new line with an energy of 6.51 keV with broad profile that is typical for relativistic iron line FeKα generated in an inclined accretion disk. Such a line configuration can be explained within the model of a double black hole system with an orbital period of the order of 6 yrs. Energies and profiles of the iron spectral lines FeKα correspond to the radiation of the accretion disks around Schwarzschild black holes with disk inclinations of 6 and 20 degrees. Some additional observations are needed to get a final conclusion about the structure of the lines and about the presence or absence of a double black hole in the core of NGC 1194. |
Keywords: double black hole, NGC 1194 |
1.A. Vasilenko, “Defining the parameters of the active nucleus of the galaxy NGC 1194,” Bull. Kyiv Univ. Astron. 49, 29–31 (2012).
2.Ya. S. Yatskiv, O. M. Aleksandrov, I. B. Vavilova, et al., General Theory of Relativity: the Test of Time (MAO Nath. Acad. Sci. Ukraine, Kyiv, 2005) [in Ukrainian].
3.R. Antonucci, “Unified models for active galactic nuclei and quasars,” Annu. Rev. Astron. Astrophys. 31, 473–521 (1993).
https://doi.org/10.1146/annurev.aa.31.090193.002353
4.J. M. Bardeen and J. A. Petterson, “The lense-thirring effect and accretion disks around Kerr black holes,” Astrophys. J., Lett. 195, 65–67 (1975).
https://doi.org/10.1086/181711
5.E. Bon, P. Jovanovic, P. Marziani, et al., “The first spectroscopically resolved sub-parsec orbit of a supermassive binary black hole”, Astrophys. J. 759, 118–126 (2012).
https://doi.org/10.1088/0004-637X/759/2/118
6.G. Cusumano, V. La Parola, A. Segreto, et al., “The Palermo Swift-BAT hard X-ray catalogue. III. Results after 54 months of sky survey,” Astron. Astron. Astrophys. 524, 64–101 (2010).
https://doi.org/10.1051/0004-6361/201015249
7.R. P. Deo, D. M. Crenshaw, S. B. Kraemer, et al., “Spitzer IRS observations of Seyfert 1.8 and 1.9 galaxies: a comparison with Seyfert 1 and Seyfert 2,” Astrophys. J. 671, 124–135 (2007).
https://doi.org/10.1086/522823
8.J. M. Dickey and F. J. Lockman, “H I in the Galaxy,” Annu. Rev. Astron. Astrophys. 28, 215–261 (1990).
https://doi.org/10.1146/annurev.aa.28.090190.001243
9.A. C. Fabian, M. J. Rees, L. Stella, et al., “X-ray fluorescence from the inner disc in Cygnus X-1,” Mon. Not. R. Astron. Soc. 238, 729–736 (1989).
https://doi.org/10.1093/mnras/238.3.729
10.L. J. Greenhill, A. Tilak, and G. Madejski, “Revalence of high X-Ray obscuring columns among AGNs that host H2O masers,” Astrophys. J. 686, 13–16 (2008).
https://doi.org/10.1086/592782
11.S. Iguchi, T. Okuda, and H. Sudou, “A very close binary black hole in a giant elliptical galaxy 3C 66B and its black hole merger,” Astrophys. Lett. 724, 166–170 (2010).
https://doi.org/10.1088/2041-8205/724/2/L166
12.W. F. Kailey and M. J. Lebofsky, “A study of warm IRAS Seyfert galaxies,” Astrophys. J. 326, 653–661 (1988).
https://doi.org/10.1086/166124
13.P. Kalberla, W. B. Burton, D. Hartmann, et al., “The LAB survey of Galactic HI final data release of the combined LDS and IAR surveys with improved stray-radiation corrections,” Astron. Astrophys. 440, 775–782 (2005).
https://doi.org/10.1051/0004-6361:20041864
14.S. Komossa, “Observational evidence for supermassive black hole binaries,” AIP Conf. Proc. 686, 161–174 (2003).
https://doi.org/10.1063/1.1629428
15.C. Y. Kuo, J. A. Braatz, J. J. Condon, et al., “The megamaser cosmology project. III. Accurate masses of seven supermassive black holes in active galaxies with circumnuclear megamaser disks,” Astrophys. J. 727, 20–35 (2011).
https://doi.org/10.1088/0004-637X/727/1/20
16.A. P. Lobanov, “Mergers and binary SMBH in the contexts of nuclear activity and galaxy evolution” Mem. Soc. Astron. Ital. 76, 164–165 (2005).
17.P. Maglaziarz and A. Zdziarski, “Angle-dependent Compton reflection of X-rays and gamma-rays” Mon. Not. R. Astron. Soc. 273, 837–848 (1995).
18.D. Porquet, J. N. Reeves, A. Markowitz, et al., “An XMM-Newton view of the X-ray flat radio-quiet quasar PG1416-129,” Astron. Astrophys. 466, 23–30 (2007).
https://doi.org/10.1051/0004-6361:20066048
19.D. Porquet, J. N. Reeves, P. Uttley, et al., “XMM-Newton observation of the Seyfert 1.8 ESO113-G010: Discovery of highly redshifted iron line at 5.4 keV,” Astron. Astrophys. 427, 101–105 (2004).
https://doi.org/10.1051/0004-6361:20041637
20.R. Protassov, A. David, A. Connors, et al., “Statistics, handle with care: detecting multiple model components with the likelihood ratio test,” Astrophys. J. 571, 545–559 (2002).
https://doi.org/10.1086/339856
21.E. Rivers, A. Markowitz, and R. Rothschild, “Spectral survey of X-ray bright active galactic nuclei from the Rossi X-ray timing explorer,” Astrophys. J. Suppl. Ser. 193(1), 3 (2011).
https://doi.org/10.1088/0067-0049/193/1/3
22.P. Severgini, A. Caccianiga, and R. Della Ceca, “A new technique to efficiently select Compton-thick AGN,” Astron. Astrophys. 542, 46–55 (2012).
https://doi.org/10.1051/0004-6361/201118417
23.R. M. Sosa-Brito, E. T.-G. Lowell, D. L. Matthew, et al., “Integral field near-infrared spectroscopy of a sample of Seyfert and LINER galaxies. I. The data,” Astrophys. J. Suppl. Ser. 136, 61–98 (2001).
https://doi.org/10.1086/321796
24.G. Theureau, N. Coudreau, N. Hallet, et al., “Kinematics of the local universe,” Astron. Astrophys. 430, 373–383 (2005).
https://doi.org/10.1051/0004-6361:20047152
25.H. D. Tran, “Hidden broad-line Seyfert 2 galaxies in the CfA and 12 μm samples”, Astrophys. J. 554, 19–23 (2001).
https://doi.org/10.1086/320926
26.J. Tueller, R. F. Mushotzky, S. Barthelmyet, et al., “Swift BAT survey of AGNs,” Astrophys. J. 681, 113–127 (2008).
https://doi.org/10.1086/588458
27.T. J. Turner, I. M. George, K. Nandra, et al., “ASCA observations of type 2 Seyfert galaxies. III. Orientation and X-ray absorption,” Astrophys. J. 483, 91–101 (1998).
28.J. Wang, Z. You-Yuan, and W. Ting-Guiet, “The broad Fe K-line profile in NGC 4151,” Astrophys. J. 523, 129–132 (1999).
https://doi.org/10.1086/312268
29.S. M. Wu and T. Wang, “Reprocessed emission from warped accretion disks,” AIP Conf. Proc. 968, 423–425 (2007).
https://doi.org/10.1063/1.2840448
30.L. M. Winter, F. M. Richard, S. R. Christopher, et al., “X-ray spectral properties of the BAT AGN sample,” Astrophys. J. 690, 1322–1349 (2009).
https://doi.org/10.1088/0004-637X/690/2/1322
31.Q. Yu and Y. Lu, “FeK α line: A tool to probe massive binary black holes in Active Galactic Nuclei?” Astron. Astrophys. 377, 17–22 (2001).
https://doi.org/10.1051/0004-6361:20011064