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arXiv · 1708.03546

Evidence for a radiatively driven disc-wind in PDS 456?

G. A. Matzeu·J. N. Reeves·V. Braito·E. Nardini·D. E. McLaughlin·A. P. Lobban·F. Tombesi·M. T. Costa
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Abstract

We present a newly discovered correlation between the wind outflow velocity and the X-ray luminosity in the luminous ($L_{\rm bol}\sim10^{47}\,\rm erg\,s^{-1}$) nearby ($z=0.184$) quasar PDS\,456. All the contemporary XMM-Newton, NuSTAR and Suzaku observations from 2001--2014 were revisited and we find that the centroid energy of the blueshifted Fe\,K absorption profile increases with luminosity. This translates into a correlation between the wind outflow velocity and the hard X-ray luminosity (between 7--30\,keV) where we find that $v_{\rm w}/c \propto L_{7-30}^{\gamma}$ where $\gamma=0.22\pm0.04$. We also show that this is consistent with a wind that is predominately radiatively driven, possibly resulting from the high Eddington ratio of PDS\,456.

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G. A. Matzeu, J. N. Reeves, V. Braito, E. Nardini, D. E. McLaughlin, A. P. Lobban, F. Tombesi, M. T. Costa. 2017-08-11. Evidence for a radiatively driven disc-wind in PDS 456?. https://doi.org/10.1093/mnrasl/slx129

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