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Complex Absorption Hides a Type II QSO in IRAS 13197-1627

Mauro Dadina·Massimo Cappi
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Abstract

We report on the analysis of a BeppoSAX observation of IRAS 13197-1627. The complexity of the broad band (0.3-100 keV) spectrum of the source prevents us from selecting from two possible best-fit models, i.e. one based on a partial covering and the other on a reflection dominated scenario. Whatever the best fit model, the data imply that: 1) the primary spectrum is heavily obscured by at least two absorbers with column densities of the order of 5x10^23 cm-2 and >2x10^24 cm-2; 2) the intrinsic 2-10 keV luminosity of the source is at least \~2x10^44 erg/s thus making IRAS 13197-1627 a type-II QSO (more precisely a type 1.8 QSO) rather than a Seyfert 1.8 galaxy as previously classified. Furthermore, there is marginal evidence of an absorption line at E $\sim$7.5 keV suggesting a possible outflow with v~0.1c similar to recent findings on other QSOs and Seyferts.

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Mauro Dadina, Massimo Cappi. 2003-10-09. Complex Absorption Hides a Type II QSO in IRAS 13197-1627. https://doi.org/10.1051/0004-6361%3A20031561

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