skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A COMPTON-THICK WIND IN THE HIGH-LUMINOSITY QUASAR, PDS 456

Journal Article · · Astrophysical Journal
 [1];  [2];  [3]; ; ;  [4];  [5];  [6];  [7]
  1. Astrophysics Group, School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire, ST5 5BG (United Kingdom)
  2. Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)
  3. Department of Physics and Astronomy, Johns Hopkins University, N Charles Street, Baltimore, MD 21218 (United States)
  4. Astrophysics Division, NASA Goddard Space Flight Center, Greenbelt Road, Greenbelt, MD 20771 (United States)
  5. Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)
  6. Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom)
  7. Department of Physics, Technion, Haifa 32000 (Israel)

PDS 456 is a nearby (z = 0.184), luminous (L {sub bol} {approx} 10{sup 47} erg s{sup -1}) type I quasar. A deep 190 ks Suzaku observation in 2007 February revealed the complex, broadband X-ray spectrum of PDS 456. The Suzaku spectrum exhibits highly statistically significant absorption features near 9 keV in the quasar rest frame. We show that the most plausible origin of the absorption is from blueshifted resonance (1s-2p) transitions of hydrogen-like iron (at 6.97 keV in the rest frame). This indicates that a highly ionized outflow may be present moving at near relativistic velocities ({approx} 0.25c). A possible hard X-ray excess is detected above 15 keV with the Hard X-ray Detector (at 99.8% confidence), which may arise from high column density gas (N {sub H} > 10{sup 24} cm{sup -2}) partially covering the X-ray emission, or through strong Compton reflection. Here we propose that the iron K-shell absorption in PDS 456 is associated with a thick, possibly clumpy outflow, covering about 20% of 4{pi} steradian solid angle. The outflow is likely launched from the inner accretion disk, within 15-100 gravitational radii of the black hole. The kinetic power of the outflow may be similar to the bolometric luminosity of PDS 456. Such a powerful wind could have a significant effect on the co-evolution of the host galaxy and its supermassive black hole, through feedback.

OSTI ID:
21313679
Journal Information:
Astrophysical Journal, Vol. 701, Issue 1; Other Information: DOI: 10.1088/0004-637X/701/1/493; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
Country of Publication:
United States
Language:
English