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The Compton Hump and Variable Blue Wing in the Extreme Low-Flux NuSTAR Observations of 1H0707-495The narrow-line Seyfert I galaxy, 1H0707−495, has been well observed in the 0.3-10 kiloelectronvolt band, revealing a dramatic drop in flux in the iron K-alpha band, a strong soft excess, and short time-scale reverberation lags associated with these spectral features. In this paper, we present the first results of a deep 250-kilosecond NuSTAR (Nuclear Spectroscopic Telescope Array) observation of 1H0707−495, which includes the first sensitive observations above 10 kiloelectronvolts. Even though the NuSTAR observations caught the source in an extreme low-flux state, the Compton hump is still significantly detected. NuSTAR, with its high effective area above 7 kiloelectronvolts, clearly detects the drop in flux in the iron K-alpha band, and by comparing these observations with archival XMM-Newton observations, we find that the energy of this drop increases with increasing flux. We discuss possible explanations for this, the most likely of which is that the drop in flux is the blue wing of the relativistically broadened iron K-alpha emission line. When the flux is low, the coronal source height is low, thus enhancing the most gravitationally red-shifted emission.
Document ID
20160010544
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Kara, E.
(Cambridge Univ. Cambridge, United Kingdom)
Fabian, A.C.
(Cambridge Univ. Cambridge, United Kingdom)
Lohfink, A. M.
(Cambridge Univ. Cambridge, United Kingdom)
Parker, M. L.
(Cambridge Univ. Cambridge, United Kingdom)
Walton, D. J.
(California Inst. of Tech. Pasadena, CA, United States)
Boggs, S. E.
(California Univ. Berkeley, CA, United States)
Christensen, F. E.
(Technical Univ. of Denmark Lyngby, Denmark)
Hailey, C. J.
(Columbia Univ. New York, NY, United States)
Harrison, F. A.
(California Inst. of Tech. Pasadena, CA, United States)
Matt, G.
(Universita degli Studi Roma Tre Rome, Italy)
Reynolds, C. S.
(Maryland Univ. College Park, MD, United States)
Stern, D.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Zhang, W. W.
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Date Acquired
August 23, 2016
Publication Date
March 17, 2015
Publication Information
Publication: Monthly Notices of the Royal Astronomical Society
Publisher: Royal Astromoical Society
Volume: 449
Issue: 1
Subject Category
Astronomy
Astrophysics
Report/Patent Number
GSFC-E-DAA-TN35008
Funding Number(s)
CONTRACT_GRANT: NNG08FD60C
Distribution Limits
Public
Copyright
Other
Keywords
black hole physics a galaxies: active a galaxies: individual: 1H0707a'495 a

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