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Measuring the Obscuring Column of a Disk Megamaser AGN in a Nearby Merger

Masini, A. and Comastri, A. and Hickox, R. C. and Koss, M. and Civano, F. and Brightman, M. and Brusa, M. and Lanzuisi, G. (2019) Measuring the Obscuring Column of a Disk Megamaser AGN in a Nearby Merger. Astrophysical Journal, 882 (2). Art. No. 83. ISSN 1538-4357. doi:10.3847/1538-4357/ab3214.

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Active galactic nuclei (AGNs) hosting disk water megamasers are well known to be obscured by large amounts of gas, likely due to the presence along the line of sight of an almost edge-on disky structure orbiting the supermassive black hole. Correcting for the high obscuration is crucial to infer parameters intrinsic to the source, like its luminosity. We present a broadband X-ray spectral analysis of a water megamaser AGN in an early merger (NGC 5765B), combining Chandra and NuSTAR data. NGC 5765B is highly Compton-thick and reflection-dominated, following the general trend among disk megamasers. Combining the exquisite black hole mass from masers with our X-ray spectroscopy, the Eddington ratio of the megamaser is estimated to be in the 2%–14% range, and its robustness is confirmed through SED fitting.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Masini, A.0000-0002-7100-9366
Comastri, A.0000-0003-3451-9970
Hickox, R. C.0000-0003-1468-9526
Koss, M.0000-0002-7998-9581
Civano, F.0000-0002-2115-1137
Brightman, M.0000-0002-8147-2602
Brusa, M.0000-0002-5059-6848
Lanzuisi, G.0000-0001-9094-0984
Additional Information:© 2019 The American Astronomical Society. Received 2019 May 1; revised 2019 July 8; accepted 2019 July 11; published 2019 September 4. We thank the anonymous referee for useful suggestions that improved the clarity of the paper, and M. Baloković for useful help and suggestions on Borus02 modeling. This work was supported under NASA Contract NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has also made use of data obtained from the Chandra Data Archive and the Chandra Source Catalog, and software provided by the Chandra X-ray Center (CXC). A.M. and R.C.H. acknowledge support by the NSF through grant No. 1554584, and by NASA through grant No. NNX15AP24G and Chandra GO award GO7-18130X. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. A.C., M.B., and G.L. acknowledge support from the ASI/INAF grant I/037/12/0-011/13. Facilities: Chandra - , NuSTAR. - Software: CIAO (Fruscione et al. 2006), NuSTARDAS, XSPEC (Arnaud 1996).
Group:NuSTAR, Space Radiation Laboratory
Funding AgencyGrant Number
Agenzia Spaziale Italiana (ASI)I/037/12/0-011/13
Subject Keywords:galaxies: active – methods: observational – techniques: spectroscopic – X-rays: general
Issue or Number:2
Record Number:CaltechAUTHORS:20190812-145519174
Persistent URL:
Official Citation:A. Masini et al 2019 ApJ 882 83
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:97797
Deposited By: Tony Diaz
Deposited On:12 Aug 2019 22:22
Last Modified:16 Nov 2021 17:34

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