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Multiwavelength Observations of the Obscuring Wind in the Radio-quiet Quasar MR 2251-178

Mao, Junjie and Kriss, G. A. and Landt, H. and Mehdipour, M. and Kaastra, J. S. and Miller, J. M. and Stern, D. and Gallo, L. C. and Gonzalez, A. G. and Simon, J. J. and Djorgovski, S. G. and Anand, S. and Kasliwal, Mansi M. and Karambelkar, V. (2022) Multiwavelength Observations of the Obscuring Wind in the Radio-quiet Quasar MR 2251-178. Astrophysical Journal, 940 (1). Art. No. 41. ISSN 0004-637X. doi:10.3847/1538-4357/ac99de.

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Obscuring winds driven away from active supermassive black holes are rarely seen due to their transient nature. They have been observed with multiwavelength observations in a few Seyfert 1 galaxies and one broad absorption line radio-quiet quasar so far. An X-ray obscuration event in MR 2251-178 was caught in late-2020, which triggered multiwavelength (near-IR (NIR) to X-ray) observations targeting this radio-quiet quasar. In the X-ray band, the obscurer leads to a flux drop in the soft X-ray band from late-2020 to early-2021. X-ray obscuration events might have a quasi-period of two decades considering earlier events in 1980 and 1996. In the UV band, a forest of weak blueshifted absorption features emerged in the blue wing of Lyα λ1216 in late-2020. Our XMM-Newton, NuSTAR, and Hubble Space Telescope/COS observations are obtained simultaneously; hence, the transient X-ray obscuration event is expected to account for the UV outflow, although they are not necessarily caused by the same part of the wind. Both blueshifted and redshifted absorption features were found for He ɪ λ10830, but no previous NIR spectra are available for comparison. The X-ray observational features of MR 2251-178 shared similarities with some other type 1 active galactic nuclei (AGNs) with obscuring wind. However, observational features in the UV to NIR bands are distinctly different from those seen in other AGN with obscuring winds. A general understanding of the observational variety and the nature of obscuring wind is still lacking.

Item Type:Article
Related URLs:
URLURL TypeDescription
Mao, Junjie0000-0001-7557-9713
Kriss, G. A.0000-0002-2180-8266
Mehdipour, M.0000-0002-4992-4664
Kaastra, J. S.0000-0001-5540-2822
Miller, J. M.0000-0003-2869-7682
Stern, D.0000-0003-2686-9241
Gonzalez, A. G.0000-0003-3678-5033
Djorgovski, S. G.0000-0002-0603-3087
Anand, S.0000-0003-3768-7515
Kasliwal, Mansi M.0000-0002-5619-4938
Karambelkar, V.0000-0003-2758-159X
Additional Information:We thank the referee for providing useful feedback to improve the quality of this work. A reproduction package is available at Zenodo DOI: 10.5281/zenodo.7226804. This package includes data and scripts used to reproduce the fitting results and figures presented here. This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and the USA (NASA). This work was supported by NASA through a grant for HST program number 16465 from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. This research was supported under NASA contract No. NNG08FD60C, and has made use of data obtained with the NuSTAR mission, a project led by the California Institute of Technology (Caltech), managed by the Jet Propulsion Laboratory (JPL) and funded by NASA. We thank the Swift Science Operations team for approving Swift target-of-opportunity observations in 2020 August and December, as well as 2021 May. We thank C. Leitherer for approving the Director's Discretionary program, N. Indriolo and T. Royle for technical support and executing the HST observation. We thank N. Schartel for approving the XMM-Newton directory's discretionary time observation. We thank F. Harrison for approving the NuSTAR Target of Opportunity. We also thank the HST, XMM, and NuSTAR teams for coordinating the observations. SRON is supported financially by NWO, the Netherlands Organization for Scientific Research. J.M. acknowledges useful discussions with M. S. Brotherton, P. Du, D. Bao, Z. Liu, and S. Li. H.L. acknowledges a Daphne Jackson Fellowship sponsored by the Science and Technology Facilities Council (STFC), UK. M.M.K. acknowledges generous support from the David and Lucille Packard Foundation. Facilities: IRTF(SpeX) - Infrared Telescope Facility, Gemini(GNIRS) - , Keck(LRIS) - , Hale(TSpec and DBSP) - Palomar Observatory's 5.1m Hale Telescope, HST(COS and FOS) - Hubble Space Telescope satellite, FUSE - Far Ultraviolet Spectroscopic Explorer satellite, Swift(XRT and UVOT) - Swift Gamma-Ray Burst Mission, XMM - Newton X-Ray Multimirror Mission satellite, NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission. Software: astropy (Astropy Collaboration et al. 2013), SPEX v3.05.00 (Kaastra et al. 1996, 2018b), Cloudy v17 (Ferland et al. 2017).
Group:Astronomy Department
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Science and Technology Facilities Council (STFC)UNSPECIFIED
David and Lucile Packard FoundationUNSPECIFIED
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ID Code:118194
Deposited By: Research Services Depository
Deposited On:23 Dec 2022 19:29
Last Modified:23 Dec 2022 19:29

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