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A fast and long-lived outflow from the supermassive black hole in NGC 5548

Kaastra, J. S. and Harrison, F. A. (2014) A fast and long-lived outflow from the supermassive black hole in NGC 5548. Science, 345 (6192). pp. 64-68. ISSN 0036-8075. doi:10.1126/science.1253787.

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Supermassive black holes in the nuclei of active galaxies expel large amounts of matter through powerful winds of ionized gas. The archetypal active galaxy NGC 5548 has been studied for decades, and high-resolution x-ray and ultraviolet (UV) observations have previously shown a persistent ionized outflow. An observing campaign in 2013 with six space observatories shows the nucleus to be obscured by a long-lasting, clumpy stream of ionized gas not seen before. It blocks 90% of the soft x-ray emission and causes simultaneous deep, broad UV absorption troughs. The outflow velocities of this gas are up to five times faster than those in the persistent outflow, and, at a distance of only a few light days from the nucleus, it may likely originate from the accretion disk.

Item Type:Article
Related URLs:
URLURL TypeDescription DOIArticle Materials Paper
Kaastra, J. S.0000-0001-5540-2822
Harrison, F. A.0000-0003-2992-8024
Additional Information:© 2014 American Association for the Advancement of Science. 24 March 2014; accepted 9 June 2014; Published online 19 June 2014. The data used in this research are stored in the public archives of the international space observatories involved: XMM-Newton, HST, Swift, NuSTAR, INTEGRAL, and Chandra. We acknowledge support by the International Space Science Institute in Bern; the Netherlands Organization for Scientific Research; NASA HST program 13184 from the Space Telescope Science Institute, which is operated by Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555; the UK Science and Technology Facilities Council; the French Centre National d’Etudes Spatiales, CNRS/Project International de Coopération Scientific and CNRS/Programme National Hautes Énergies; Vicerrectoría de Investigación y Desarrollo Tecnológico (Chile); Israel’s Ministry of Science, Technology, and Space, Israel Science Foundation (1163/10), and Israeli Centers of Research Excellence program (1937/12); the Swiss National Science Foundation; the Agenzia Spaziale Italiana grant INAF I/037/12/0-011/13 and INAF/Project for International Scientific Cooperation; NSF grant AST-1008882; and European Union Marie Curie contract FP-PEOPLE-2012-IEF-331095. We thank S. Paniagua for help with Fig. 4.
Group:NuSTAR, Space Radiation Laboratory
Funding AgencyGrant Number
International Space Science InstituteUNSPECIFIED
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)UNSPECIFIED
Science and Technology Facilities Council (STFC)UNSPECIFIED
Centre National d'Études Spatiales (CNES)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Vicerrectoría de Investigación y Desarrollo TecnológicoUNSPECIFIED
Israel Science Foundation1163/10
Israel Science Foundation1937/12
Swiss National Science Foundation (SNSF)UNSPECIFIED
Agenzia Spaziale Italiana (ASI)I/037/12/0-011/13
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Marie Curie FellowshipFP-PEOPLE-2012-IEF-331095
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory2014-45
Issue or Number:6192
Record Number:CaltechAUTHORS:20140728-091348328
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Official Citation:Kaastra, J. S., Kriss, G. A., Cappi, M., Mehdipour, M., Petrucci, P.-O., Steenbrugge, K. C., . . . Whewell, M. (2014). A fast and long-lived outflow from the supermassive black hole in NGC 5548. Science, 345(6192), 64-68. doi: 10.1126/science.1253787
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:47515
Deposited On:28 Jul 2014 18:09
Last Modified:10 Nov 2021 17:40

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