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arXiv · 0906.0312

A Compton-thick Wind in the High Luminosity Quasar, PDS 456

J. N. Reeves·P. T. O'Brien·V. Braito·E. Behar·L. Miller·T. J. Turner·A. C. Fabian·S. Kaspi·R. Mushotzky·M. Ward
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Abstract

PDS 456 is a nearby (z=0.184), luminous (L_bol ~10^47 erg/s) type I quasar. A deep 190 ks Suzaku observation in February 2007 revealed the complex, broad band 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 blue-shifted 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 (~0.25c). A possible hard X-ray excess is detected above 15 keV with HXD (at 99.8% confidence), which may arise from high column density gas (Nh>10^24cm^-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 $4π$ 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.

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J. N. Reeves, P. T. O'Brien, V. Braito, E. Behar, L. Miller, T. J. Turner, A. C. Fabian, S. Kaspi, R. Mushotzky, M. Ward. 2009-06-01. A Compton-thick Wind in the High Luminosity Quasar, PDS 456. https://doi.org/10.1088/0004-637x%2F701%2F1%2F493

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