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arXiv · 1609.00374

The Phoenix galaxy as seen by NuSTAR

A. Masini·A. Comastri·S. Puccetti·M. Baloković·P. Gandhi·M. Guainazzi·F. E. Bauer·S. E. Boggs·P. G. Boorman·M. Brightman·F. E. Christensen·W. W. Craig·D. Farrah·C. J. Hailey·F. A. Harrison·M. J. Koss·S. M. LaMassa·C. Ricci·D. Stern·D. J. Walton·W. W. Zhang
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Abstract

Aims. We study the long-term variability of the well-known Seyfert 2 galaxy Mrk 1210 (a.k.a. UGC 4203, or the Phoenix galaxy). Methods. The source was observed by many X-ray facilities in the last 20 years. Here we present a NuSTAR observation and put the results in context of previously published observations. Results. NuSTAR observed Mrk 1210 in 2012 for 15.4 ks. The source showed Compton-thin obscuration similar to that observed by Chandra, Suzaku, BeppoSAX and XMM-Newton over the past two decades, but different from the first observation by ASCA in 1995, in which the active nucleus was caught in a low flux state - or obscured by Compton-thick matter, with a reflection-dominated spectrum. Thanks to the high-quality hard X-ray spectrum obtained with NuSTAR and exploiting the long-term spectral coverage spanning 16.9 years, we can precisely disentangle the transmission and reflection components and put constraints on both the intrinsic long-term variability and hidden nucleus scenarios. In the former case, the distance between the reflector and the source must be at least ~ 2 pc, while in the latter one the eclipsing cloud may be identified with a water maser-emitting clump.

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A. Masini, A. Comastri, S. Puccetti, M. Baloković, P. Gandhi, M. Guainazzi, F. E. Bauer, S. E. Boggs, P. G. Boorman, M. Brightman, F. E. Christensen, W. W. Craig, D. Farrah, C. J. Hailey, F. A. Harrison, M. J. Koss, S. M. LaMassa, C. Ricci, D. Stern, D. J. Walton, W. W. Zhang. 2016-09-01. The Phoenix galaxy as seen by NuSTAR. https://doi.org/10.1051/0004-6361/201629444

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