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arXiv · 1205.0189

A 10 kpc Scale Seyfert Galaxy Outflow: HST/COS Observations of IRAS F22456-5125

Benoit Borguet·Doug Edmonds·Nahum Arav·Jay Dunn·Gerard A. Kriss
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Abstract

We present analysis of the UV-spectrum of the low-z AGN IRAS-F22456-5125 obtained with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The spectrum reveals six main kinematic components, spanning a range of velocities of up to 800 km s-1, which for the first time are observed in troughs associated with CII, CIV, NV, SiII, SiIII, SiIV and SIV. We also obtain data on the OVI troughs, which we compare to those available from an earlier FUSE epoch. Column densities measured from these ions allow us to derive a well-constrained photoionization solution for each outflow component. Two of these kinematic components show troughs associated with transitions from excited states of SiII\ and CII. The number density inferred from these troughs, in combination with the deduced ioinization parameter, allows us to determine the distance to these outflow components from the central source. We find these components to be at a distance of ~ 10 kpc. The distances and the number densities derived are consistent with the outflow being part of a galactic wind.

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Benoit Borguet, Doug Edmonds, Nahum Arav, Jay Dunn, Gerard A. Kriss. 2012-05-01. A 10 kpc Scale Seyfert Galaxy Outflow: HST/COS Observations of IRAS F22456-5125. https://doi.org/10.1088/0004-637x/751/2/107

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