Now showing items 1-8 of 8

    • A Chandra Survey of Broad Absorption Line Quasars 

      Green, Paul J.; Aldcroft, Thomas L.; Mathur, Smita; Wilkes, Belinda Jane; Elvis, Martin (IOP Publishing, 2001)
      We have carried out a survey with the Chandra X-Ray Observatory of a sample of 10 bright broad absorption line (BAL) quasars (QSOs). Eight of 10 sources are detected. The six brightest sources have only high-ionization ...
    • Clues to Quasar Broad-Line Region Geometry and Kinematics 

      Vestergaard, M.; Wilkes, Belinda Jane; Barthel, P. D. (IOP Publishing, 2000)
      We present evidence that the high-velocity C IV λ1549 emission-line gas of radio-loud quasars may originate in a disklike configuration, in close proximity to the accretion disk often assumed to emit the low-ionization ...
    • An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zwicky 1 

      Vestergaard, M.; Wilkes, Belinda Jane (IOP Publishing, 2001)
      We present an empirical template spectrum suitable for fitting and subtracting/studying the Fe II and Fe III emission lines in the rest frame ultraviolet spectra of quasars and active galactic nuclei, the first empirical ...
    • Investigation of the Relation between the Spectral Energy Distributions and the Emission Lines in Low‐Redshift Quasars 

      Wilkes, Belinda Jane; Kuraszkiewicz, Joanna; Green, Paul J.; Mathur, Smita; McDowell, Jonathan Christopher (IOP Publishing, 1999)
      We investigate the relations between the observed emission-line strengths, widths, and continuum properties of a sample of 41 low-redshift (z<1) quasars for which contemporaneous IR/soft X-ray spectral energy distributions ...
    • [O II] Emission, Eigenvector 1, and Orientation in Radio-quiet Quasars 

      Kuraszkiewicz, Joanna; Wilkes, Belinda Jane; Brandt, W. N.; Vestergaard, M. (IOP Publishing, 2000)
      We present supportive evidence that the Boroson & Green eigenvector 1 is not driven by source orientation and further that both [O III] λ5007 and [O II] λ3727 are isotropically emitted in the radio-quiet sample of bright ...
    • The PG X-Ray QSO Sample: Links between the Ultraviolet–X-Ray Continuum and Emission Lines 

      Wills, Beverley J.; Laor, A.; Brotherton, M. S.; Wills, D.; Wilkes, Belinda Jane; Ferland, G. J.; Shang, Zhaohui (IOP Publishing, 1999)
      Two sets of relationships relate QSO UV to soft X-ray continua with the broad-line region. These are (i) the Baldwin relationships, which are inverse relationships between the broad-line equivalent width and the continuum ...
    • Suzaku Monitoring of the Iron K Emission Line in the Type 1 Active Galactic Nucleus Ngc 5548 

      Liu, Yuan; Elvis, Martin S.; McHardy, Ian M.; Grupe, Dirk; Wilkes, Belinda Jane; Reeves, James; Brickhouse, Nancy S; Krongold, Yair; Mathur, Smita; Minezaki, Takeo; Nicastro, Fabrizio; Yoshii, Yuzuru; Zhang, Shuang Nan (IOP Publishing, 2010)
      We present seven sequential weekly observations of NGC 5548 conducted in 2007 with the Suzaku X-ray Imaging Spectrometer (XIS) in the 0.2–12 keV band and Hard X-ray Detector (HXD) in the 10–600 keV band. The iron Kα line ...
    • Suzaku Monitoring of the Seyfert 1 Galaxy Ngc 5548: Warm Absorber Location and Its Implication for Cosmic Feedback 

      Krongold, Y.; Elvis, Martin S.; Andrade-Velazquez, M.; Nicastro, F.; Mathur, S.; Reeves, J. N.; Brickhouse, Nancy S; Binette, L.; Jimenez-Bailon, E.; Grupe, D.; Liu, Y.; McHardy, I. M.; Minezaki, T.; Yoshii, Y.; Wilkes, Belinda Jane (IOP Publishing, 2010)
      We present seven sequential weekly observations of NGC 5548 conducted in 2007 with the Suzaku X-ray Imaging Spectrometer (XIS) in the 0.2–12 keV band and Hard X-ray Detector (HXD) in the 10–600 keV band. The iron Kα line ...