Rosat Pspc Observations of the Infrared Quasar Iras 13349+2438: Evidence for a Warm Absorber with Internal Dust

Abstract

We present spatial, temporal and spectral analyses of ROSAT Position Sensitive Proportional Counter (PSPC) observations of the infrared loud quasar IRAS 13349+2438. IRAS 13349+2438 is the archetypal highly-polarized radio-quiet QSO and has an op-tical/infrared luminosity of 2 10 46 erg s 1. We detect variability in the ROSAT count rate by a factor of 4.1 in about one year, and there is also evidence for 25 per cent variability within one week. We nd no evidence for large intrinsic cold absorption of soft X-rays. These two facts have important consequences for the scattering-plus-transmission model of this object which was developed to explain its high wavelength-dependent polarization and other properties. The soft X-ray variability makes electron scattering of most of the soft X-rays diicult without a very peculiar scattering mirror. The lack of signiicant intrinsic cold X-ray absorption together with the large observed E(B V) suggests either a very peculiar system geometry or, more probably, absorption by warm ionized gas with internal dust. There is evidence for an ionized oxygen edge in the X-ray spectrum. IRAS 13349+2438 has many properties that are similar to those of`narrow-line' Seyfert 1s.

Cite this paper

@inproceedings{Brandt1995RosatPO, title={Rosat Pspc Observations of the Infrared Quasar Iras 13349+2438: Evidence for a Warm Absorber with Internal Dust}, author={Nelli Brandt and Andrew C. Fabian and K . A . Pounds}, year={1995} }