XMM–Newton first X-ray detection of the low-ionization broad absorption line quasar PG 1700+518

7 páginas, 5 figuras, 2 tablas.-- El Pdf del artículo es la versión pre-print: arXiv:1104.2003v1We report the first high-energy detection of PG 1700+518, a well-known low-ionization broad absorption line quasar (quasi-stellar object, QSO). Due to previous X-ray non-detection, it was classified as soft X-ray weak QSO. We observed PG 1700+518 with XMM–Newton for about 60 ks divided in three exposures. The spectrum below 2 keV is very steep, Γ∼ 2.4–3.8, while at higher energies the extremely flat emission (photon index Γ∼ 0.15, when modelled with a power law) suggests the presence of strong absorption (NH, pl∼ 2 × 1023 cm−2, Γ fixed to 1.8) or a reflection-dominated continuum. The broad-band flux is consistent with previous non-detection. Simultaneous European Photon Imaging Camera (EPIC) and Optical Monitor (OM) data confirm its X-ray weakness (observedαox∼−2.2). The level of obscuration derived from the X-ray spectra of PG 1700+518 cannot explain its soft X-ray nuclear weakness unless a column density of NH≳ 2 × 1024 cm−2 is present.LB acknowledges support from the SpanishMinistry of Science and Innovation through a ‘Juan de la Cierva’ fellowship. Financial support for this work was provided by the Spanish Ministry of Science and Innovation, through research grant AYA2009-08059. Support from the Italian Space Agency is acknowledged by EP (contract ASI/INAF I/088/06/0) and CV (contracts I/088/06/0 and I/009/10/0).Peer reviewe

XMM-Newton first X-ray detection of the low-ionization broad absorption line quasar PG 1700+518

We report the first high-energy detection of PG 1700+518, a well-known low-ionization broad absorption line quasar (quasi-stellar object, QSO). Due to previous X-ray non-detection, it was classified as soft X-ray weak QSO. We observed PG 1700+518 with XMM-Newton for about 60 ks divided in three exposures. The spectrum below 2 keV is very steep, \u393\u2dc 2.4-3.8, while at higher energies the extremely flat emission (photon index \u393\u2dc 0.15, when modelled with a power law) suggests the presence of strong absorption (NH, pl\u2dc 2 7 10^23 cm-2, \u393 fixed to 1.8) or a reflection-dominated continuum. The broad-band flux is consistent with previous non-detection. Simultaneous European Photon Imaging Camera (EPIC) and Optical Monitor (OM) data confirm its X-ray weakness (observed\u3b1ox\u2dc-2.2). The level of obscuration derived from the X-ray spectra of PG 1700+518 cannot explain its soft X-ray nuclear weakness unless a column density of NH 73 2 7 10^24 cm-2 is present

XMM–Newton first X-ray detection of the low-ionization broad absorption line quasar PG 1700+518

7 páginas, 5 figuras, 2 tablas.-- El Pdf del artículo es la versión pre-print: arXiv:1104.2003v1We report the first high-energy detection of PG 1700+518, a well-known low-ionization broad absorption line quasar (quasi-stellar object, QSO). Due to previous X-ray non-detection, it was classified as soft X-ray weak QSO. We observed PG 1700+518 with XMM–Newton for about 60 ks divided in three exposures. The spectrum below 2 keV is very steep, Γ∼ 2.4–3.8, while at higher energies the extremely flat emission (photon index Γ∼ 0.15, when modelled with a power law) suggests the presence of strong absorption (NH, pl∼ 2 × 1023 cm−2, Γ fixed to 1.8) or a reflection-dominated continuum. The broad-band flux is consistent with previous non-detection. Simultaneous European Photon Imaging Camera (EPIC) and Optical Monitor (OM) data confirm its X-ray weakness (observedαox∼−2.2). The level of obscuration derived from the X-ray spectra of PG 1700+518 cannot explain its soft X-ray nuclear weakness unless a column density of NH≳ 2 × 1024 cm−2 is present.LB acknowledges support from the SpanishMinistry of Science and Innovation through a ‘Juan de la Cierva’ fellowship. Financial support for this work was provided by the Spanish Ministry of Science and Innovation, through research grant AYA2009-08059. Support from the Italian Space Agency is acknowledged by EP (contract ASI/INAF I/088/06/0) and CV (contracts I/088/06/0 and I/009/10/0).Peer reviewe