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FUSE Observations of the Narrow-Line Seyfert 1 Galaxy Arakelian 564

P. Romano·S. Mathur·R. W. Pogge·B. M. Peterson·J. Kuraszkiewicz
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Abstract

We present a 63 ks FUSE observation of the Narrow-Line Seyfert 1 galaxy Arakelian 564. The spectrum is dominated by the strong emission in the O VI λ\lambda1032, 1038 resonance doublet. Strong, heavily saturated absorption troughs due to Lyman series of Hydrogen, O VI and C III λ977 at velocities near the systemic redshift of Arakelian564 are also observed. We used the column densities of O VI and C III in conjunction with the published column densities of species observed in the UV and X-ray bands to derive constraints on the physical parameters of the absorber through photoionization modeling. The available data suggest that the UV and X-ray absorbers in Arakelian~564 are physically related, and possibly identical. The combination of constraints indicates that the absorber is characterized by a narrow range in total column density N_H and U, centered at log N_H ~ 21 and log U ~ -1.5, and may be spatially extended along the line of sight.

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P. Romano, S. Mathur, R. W. Pogge, B. M. Peterson, J. Kuraszkiewicz. 2002-06-18. FUSE Observations of the Narrow-Line Seyfert 1 Galaxy Arakelian 564. https://doi.org/10.1086/342403

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