Coronal properties of the luminous radio-quiet quasar QSO B2202–209
Kammoun, E. S. and Risaliti, G. and Stern, D. and Jun, H. D. and Graham, M. and Celotti, A. and Behar, E. and Elvis, M. and Harrison, F. A. and Matt, G. and Walton, D. J. (2017) Coronal properties of the luminous radio-quiet quasar QSO B2202–209. Monthly Notices of the Royal Astronomical Society, 465 (2). pp. 1665-1671. ISSN 0035-8711. https://resolver.caltech.edu/CaltechAUTHORS:20170324-073204061
We present an analysis of the joint XMM–Newton and NuSTAR observations of the radio-quiet quasar QSO B2202–209. Using an optical observation from the Hale Telescope at the Palomar Observatory, we revise the redshift of the source from the previously reported z = 1.77 to z = 0.532, and we estimate the mass of the central black hole, log (M_(BH)/M_⊙) = 9.08 ± 0.18. The X-ray spectrum of this source can be well described by a power law of photon index Γ = 1.82 ± 0.05 with E_(cut) = 152^(+103)_(−54) keV, in the rest frame of the source. Assuming a Comptonization model, we estimate the coronal temperature to be kT_e = 42 ± 3 keV and kT_e = 56 ± 3 keV for a spherical and a slab geometry, respectively. The coronal properties are comparable to the ones derived for local active galactic nuclei, despite a difference of around one order of magnitude in black hole mass and X-ray luminosity (L_(2 − 10) = 1.93 × 10^(45) erg s^(−1)). The quasar is X-ray loud, with an unusually flat observed optical-to-X-ray spectral slope α_(OX) = 1.00 ± 0.02, and has an exceptionally strong optical [O iii] line. Assuming that both the X-ray emission and the [O iii] line are isotropic, these two extreme properties can be explained by a nearly edge-on disc, leading to a reduction in the observed ultraviolet continuum light.
https://doi.org/10.1093/mnras/stw2897 DOI Article
https://academic.oup.com/mnras/article-lookup/doi/10.1093/mnras/stw2897 Publisher Article
Jun, H. D. 0000-0003-1470-5901
Matt, G. 0000-0002-2152-0916
Walton, D. J. 0000-0001-5819-3552
© 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. Received: 23 July 2016. Revision Received: 05 November 2016. Accepted: 07 November 2016. Published: 10 November 2016. This research made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA, XMM–Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, and the Hale Telescope at Palomar Observatory. This research has made use of the NuSTAR Data Analysis Software (nustardas) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We like to acknowledge S.G. Djorgovski for providing the Palomar observations. We thank the anonymous referee for comments and suggestions, which significantly contributed to improving the quality of the manuscript. EB received funding from the European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 655324. Facilities: NuSTAR, Palomar: DBSP, XMM–Newton.
NuSTAR, Space Radiation Laboratory, Astronomy Department
ESA Member States UNSPECIFIED
Hale Telescope at Palomar Observatory UNSPECIFIED
Marie Curie Fellowship 655324
galaxies: active, galaxies: nuclei, quasars: individual: QSO B2202–209, X-rays: galaxies
E. S. Kammoun, G. Risaliti, D. Stern, H. D. Jun, M. Graham, A. Celotti, E. Behar, M. Elvis, F. A. Harrison, G. Matt, D. J. Walton; Coronal properties of the luminous radio-quiet quasar QSO B2202–209. Mon Not R Astron Soc 2017; 465 (2): 1665-1671. doi: 10.1093/mnras/stw2897