Browsing by Author "Grupe, D."

Browsing by Author "Grupe, D."

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    1H 0707−495 in 2011: an X-ray source within a gravitational radius of the event horizon 
    Gallo, Luigi C.; Fabian, A. C.; Zoghbi, A.; Wilkins, D. R.; Dwelly, T.; Uttley, P.; Schartel, N.; Miniutti, G.; Grupe, D.; Komossa, S. (Oxford University Press, 2012)
    The narrow-line Seyfert 1 Galaxy 1H 0707−495 went into a low state from 2010 December to 2011 February, discovered by a monitoring campaign using the X-Ray Telescope on the Swift satellite. We triggered a 100 ks XMM–Newton ...

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    A blurred reflection interpretation for the intermediate flux state in Mrk 335 
    Gallo, Luigi C.; Bonson, K.; Fabian, A. C.; Grupe, D.; Komossa, S.; Longinotti, A. L.; Miniutti, G.; Walton, D. J.; Zoghbi, A.; Mathur, S. (Oxford University Press, 2013-01)
    As part of a long-term monitoring campaign of Mrk 335, deep XMM–Newton observations catch the narrow-line Seyfert 1 galaxy (NLS1) in a complex, intermediate flux interval as the active galaxy is transiting from low to high ...

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    Flaring from the supermassive black hole in Mrk 335 studied with Swift and NuSTAR 
    Wilkins, D. R.; Gallo, Luigi C.; Grupe, D.; Bonson, K.; Komossa, S.; Fabian, A. C. (Oxford University Press, 2015-12-21)
    Monitoring of the narrowline Seyfert 1 galaxy Markarian 335 (Mrk 335) with the Swift satellite discovered an X-ray flare beginning 2014 August 29. At the peak, the 0.5–5 keV count rate had increased from that in the low-flux ...

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    The nuclear environment of the NLS1 Mrk 335: Obscuration of the X-ray line emission by a variable outflow 
    Parker, M. L.; Longinotti, A. L.; Schartel, N.; Grupe, D.; Komossa, S.; Kriss, G.; Fabian, Andrew C.; Gallo, Luigi C.; Harrison, F. A.; Jiang, J.; Kara, E.; Krongold, Y.; Matzeu, G. A.; Pinto, C.; Santos-Lleo, M. (Royal Astronomical SocietyOxford University Press, 2019-09-12)
    We present XMM–Newton, NuSTAR, Swift, and Hubble Space Telescope observations of the Narrow-line Seyfert 1 galaxy Mrk 335 in a protracted low state in 2018 and 2019. The X-ray flux ...

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    The NuSTAR spectrum of Mrk 335: extreme relativistic effects within two gravitational radii of the event horizon 
    Parker, M. L.; Wilkins, D. R.; Fabian, A. C.; Grupe, D.; Dauser, T.; Matt, G.; Harrison, F. A.; Brenneman, L.; Boggs, S. E.; Christensen, F. E.; Gallo, Luigi C. (Oxford University Press, 2014-09-11)
    We present 3–50 keV NuSTAR observations of the active galactic nuclei Mrk 335 in a very low flux state. The spectrum is dominated by very strong features at the energies of the iron line at 5–7 keV and Compton ...

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    Properties of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies (Corrigendum) 
    Foschini, L.; Berton, M.; Caccianiga, A.; Ciroi, S.; Cracco, V.; Peterson, B. M.; Angelakis, E.; Braito, V.; Fuhrmann, L.; Gallo, Luigi C.; Grupe, D.; Järvelä, E.; Kaufmann, S.; Komossa, S.; Kovalev, Y. Y.; Lähteenmäki, A.; Lisakov, M. M.; Lister, M. L.; Mathur, S.; Richards, J. L.; Romano, P.; Sievers, A.; Tagliaferri, G.; Tammi, J.; Tibolla, O.; Tornikoski, M.; Vercellone, S.; La Mura, G.; Maraschi, L.; Rafanelli, P. (EDP Sciences, 2017-07)
    This article is an erratum for: Properties of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies (Astronomy & Astrophysics vol 575, A13, 2015).

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    The quasar PG 0844+349 in an X-ray weak state 
    Gallo, Luigi C.; Grupe, D.; Schartel, N.; Komossa, S.; Miniutti, G.; Fabian, A. C.; Santos-Lleo, M. (Oxford University Press, 2011-03)
    In 2009 March the well-studied quasar, PG 0844+349, was discovered with Swift to be in an X-ray weak state. A follow-up XMM–Newton observation several weeks later generated a good-quality spectrum of the source, showing ...

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    The rise of an ionized wind in the narrow-line Seyfert 1 galaxy Mrk 335 observed by XMM-Newton and HST 
    Gallo, Luigi C.; Longinotti, A. L.; Krongold, Y.; Kriss, G. A.; Ely, J.; Grupe, D.; Komossa, S.; Mathur, S.; Pradhan, A. (American Astronomical SocietyIOP Publishing, 2013-04-01)
    We present the discovery of an outflowing ionized wind in the Seyfert 1 galaxy Mrk 335. Despite having been extensively observed by most of the largest X-ray observatories in the last decade, this bright source was not ...

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    Studying X-ray reprocessing and continuum variability in quasars: PG 1211+143 
    Gallo, Luigi C.; Bachev, R.; Grupe, D.; Boeva, S.; Ovcharov, E.; Valcheva, A.; Semkov, E.; Georgiev, Ts. (Oxford University Press, 2009-10)
    We present the results from a monitoring campaign of the Narrow-Line Seyfert 1 galaxy PG 1211+143. The object was monitored with ground-based facilities (UBVRI photometry; from 2007 February to July) and with Swift [X-ray ...

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    Suzaku observations of Mrk 335: confronting partial covering and relativistic reflection 
    Gallo, Luigi C.; Wilkins, D. R.; Bonson, K.; Chiang, C.-Y.; Grupe, D.; Parker, M. L.; Zoghbi, A.; Fabian, A. C.; Komossa, S.; Longinotti, A. L. (Oxford University Press, 2015-01)
    We report on the deepest X-ray observation of the narrow-line Seyfert 1 galaxy Mrk 335 in the low-flux state obtained with Suzaku. The data are compared to a 2006 high-flux Suzaku observation when the source was ∼10 times ...