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arXiv · 1411.2157

Anatomy of the AGN in NGC 5548: II. The Spatial, Temporal and Physical Nature of the Outflow from HST/COS Observations

N. Arav·C. Chamberlain·G. A. Kriss·J. S. Kaastra·M. Cappi·M. Mehdipour·P. -O. Petrucci·K. C. Steenbrugge·E. Behar·S. Bianchi·R. Boissay·G. Branduardi-Raymont·E. Costantini·J. C. Ely·J. Ebrero·L. di Gesu·F. A. Harrison·S. Kaspi·J. Malzac·B. De Marco·G. Matt·K. P. Nandra·S. Paltani·B. M. Peterson·C. Pinto·G. Ponti·F. Pozo Nuñez·A. De Rosa·H. Seta·F. Ursini·C. P. de Vries·D. J. Walton·M. Whewel
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Abstract

(Abridged) Our deep multiwavelength campaign on NGC 5548 revealed an unusually strong X-ray obscuration. The resulting dramatic decrease in incident ionizing flux allowed us to construct a comprehensive physical, spatial and temporal picture for the long-studied AGN wind in this object. Here we analyze the UV spectra of the outflow acquired during the campaign as well as from four previous epochs. We find that a simple model based on a fixed total column-density absorber, reacting to changes in ionizing illumination, matches the very different ionization states seen in five spectroscopic epochs spanning 16 years. Absorption troughs from C III* appeared for the first time during our campaign. From these troughs, we infer that the main outflow component is situated at 3.5+-1 pc from the central source. Three other components are situated between 5-70 pc and two are further than 100 pc. The wealth of observational constraints and the disparate relationship of the observed X-ray and UV flux between different epochs make our physical model a leading contender for interpreting trough variability data of quasar outflows.

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N. Arav, C. Chamberlain, G. A. Kriss, J. S. Kaastra, M. Cappi, M. Mehdipour, P. -O. Petrucci, K. C. Steenbrugge, E. Behar, S. Bianchi, R. Boissay, G. Branduardi-Raymont, E. Costantini, J. C. Ely, J. Ebrero, L. di Gesu, F. A. Harrison, S. Kaspi, J. Malzac, B. De Marco, G. Matt, K. P. Nandra, S. Paltani, B. M. Peterson, C. Pinto, G. Ponti, F. Pozo Nuñez, A. De Rosa, H. Seta, F. Ursini, C. P. de Vries, D. J. Walton, M. Whewel. 2014-11-08. Anatomy of the AGN in NGC 5548: II. The Spatial, Temporal and Physical Nature of the Outflow from HST/COS Observations. https://doi.org/10.1051/0004-6361%2F201425302

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