The XMM-Newton view of three X-ray weak quasars: Iron emission and strong ionized absorption

¹ XMM-Newton Science Operations Centre, ESA, RSSD, ESAC, Apartado 50727, 28020 Madrid, Spain e-mail: Norbert.Schartel@sciops.esa.int
² Astrophysics Mission Division, ESA, SCT-SA, ESTEC, Postbus 299, 2200 AG - Noordwijk, The Netherlands

Received: 5 August 2004
Accepted: 17 November 2004

Abstract

We present the analysis of XMM-Newton observations of three X-ray weak quasars: PG 1001+054, PG 1535+547 and PG 2112+059. All objects are absorbed by ionized material showing high column densities, to , and ionization parameters, to . The spectra of PG 1535+547 require an additional partial covering by neutral material with a column density of at a covering factor of 0.96.
The spectra of PG 1535+547 show systematic residuals in the energy range from ~4 keV to ~6 keV, which are inconsistent with K_α-fluorescence-emission of neutral or ionized iron under the assumption of a Gaussian line profile. They can be described with a relativistic disk line (Laor) and establish therefore the second X-ray weak quasar with such a spectral characteristic.
Our results together with the findings of Brinkmann et al. ([CITE], A&A, 414, 107) and Piconcelli et al. ([CITE], MNRAS, 351, 161), indicate that warm absorbers characterized by high column densities and ionization parameters are typical of X-ray weak quasars. The occurrence of a variable relativistic broad Fe K_α fluorescence line in two out of the five well studied X-ray weak quasars might indicate a second general characteristic of the entire object class.
Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.