Galactic Scale Absorption Outflow in the Low Luminosity Quasar IRAS~F04250-5718: HST/COS Observations

Doug Edmonds; Benoit Borguet; Nahum Arav; Jay P. Dunn; Steve Penton; Gerard A. Kriss; Kirk Korista; Elisa Costantini; Katrien Steenbrugge; J. Ignacio Gonzalez-Serrano; Kentaro Aoki; Manuel Bautista; Ehud Behar; Chris Benn; D. Micheal Crenshaw; John Everett; Jack Gabel; Jelle Kaastra; Maxwell Moe; Jennifer Scott

arXiv · 1106.2084

Galactic Scale Absorption Outflow in the Low Luminosity Quasar IRAS~F04250-5718: HST/COS Observations

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Abstract

We present absorption line analysis of the outflow in the quasar IRAS F04250-5718. Far-ultraviolet data from the Cosmic Origins Spectrograph onboard the Hubble Space Telescope reveal intrinsic narrow absorption lines from high ionization ions (e.g., C IV, N V, and O VI) as well as low ionization ions (e.g., C II and Si III). We identify three kinematic components with central velocities ranging from ~-50 to ~-230 km/s. Velocity dependent, non-black saturation is evident from the line profiles of the high ionization ions. From the non-detection of absorption from a metastable level of C II, we are able to determine that the electron number density in the main component of the outflow is < 30 per cubic cm. Photoionization analysis yields an ionization parameter log U ~ -1.6 +/- 0.2, which accounts for changes in the metallicity of the outflow and the shape of the incident spectrum. We also consider solutions with two ionization parameters. If the ionization structure of the outflow is due to photoionization by the active galactic nucleus, we determine that the distance to this component from the central source is > 3 kpc. Due to the large distance determined for the main kinematic component, we discuss the possibility that this outflow is part of a galactic wind.

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Doug Edmonds, Benoit Borguet, Nahum Arav, Jay P. Dunn, Steve Penton, Gerard A. Kriss, Kirk Korista, Elisa Costantini, Katrien Steenbrugge, J. Ignacio Gonzalez-Serrano, Kentaro Aoki, Manuel Bautista, Ehud Behar, Chris Benn, D. Micheal Crenshaw, John Everett, Jack Gabel, Jelle Kaastra, Maxwell Moe, Jennifer Scott. 2011-06-10. Galactic Scale Absorption Outflow in the Low Luminosity Quasar IRAS~F04250-5718: HST/COS Observations. https://arxiv.org/abs/1106.2084

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