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X-ray absorption and re-emission from an ionised outflow in the Type 1 QSO 2MASS 234449+1221

K. A. Pounds·B. J. Wilkes·K. L. Page
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Abstract

We report on the analysis of a short XMM-Newton observation of the reddened Type 1 QSO 2MASS 234449+1221 first identified in the Two Micron All-Sky Survey. The underlying X-ray continuum is found to be typical of a broad-line active galaxy, with photon index Gamma ~ 1.9. Low energy absorption can be modelled by a column N_H ~ 10^22 cm^{-2} of moderately ionised gas or a smaller column of cold gas. Addition of a soft X-ray emission component significantly improves the fit in both cases. With the assumption that the soft X-ray flux represents emission from gas photoionised by the incident X-ray continuum, a comparison of the absorbed and emitted luminosities indicates a covering factor of ~ 8-17%. The unusual opportunity to simultaneously observe and quantify ionised absorption and emission in 2MASS 234449+1221 is due to the relatively large opacity (for a Type 1 AGN) of the absorbing gas, which depresses the normally strong continuum below ~ 1 keV. A comparison of the soft X-ray emission of 2MASS 234449+1221 with that of other Type 1 and Type 2 AGN suggests the existence of an inner turbulent extension to ionised outflows, not detected in current high resolution X-ray spectra.

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K. A. Pounds, B. J. Wilkes, K. L. Page. 2005-06-29. X-ray absorption and re-emission from an ionised outflow in the Type 1 QSO 2MASS 234449+1221. https://doi.org/10.1111/j.1365-2966.2005.09365.x

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