Browsing by Author "Brandt, W. N."

Browsing by Author "Brandt, W. N."

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    Insights on the X-ray weak quasar phenomenon from XMM–Newton monitoring of PHL1092 
    Gallo, Luigi C.; Miniutti, G.; Brandt, W. N.; Schneider, D. P.; Fabian, A. C.; Boller, Th. (Royal Astronomical SocietyOxford University Press, 2012)
    PHL 1092 is a z ∼ 0.4 high-luminosity counterpart of the class of Narrow-Line Seyfert 1 galaxies. In 2008, PHL 1092 was found to be in a remarkably low X-ray flux state during an XMM–Newton observation. Its 2 keV flux ...

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    PHL 1092 as a transient extreme X-ray weak quasar 
    Gallo, Luigi C.; Miniutti, G.; Fabian, A. C.; Brandt, W. N.; Boller, Th. (Royal Astronomical SocietyOxford University Press, 2009)
    We report a dramatic variability event in the X-ray history of the narrow-line quasar PHL 1092 (z = 0.396). Our latest 2008 XMM-Newton observation reveals a flux drop of ∼200 with respect to the previous observation performed ...

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    Revealing structure and evolution within the corona of the Seyfert galaxy I Zw 1 
    Wilkins, D. R.; Gallo, Luigi C.; Silva, C. V.; Costantini, E.; Brandt, W. N.; Kriss, G. A. (Oxford University Press, 2017-11)
    X-ray spectral timing analysis is presented of XMM–Newton observations of the narrow-line Seyfert 1 galaxy I Zwicky 1 taken in 2015 January. After exploring the effect of background flaring on timing analyses, X-ray ...