Coordinated X-ray and UV absorption within the accretion disk wind of the active galactic nucleus PG 1126-041

¹ Centro de Astrobiología (CAB), CSIC-INTA, Camino Bajo del Castillo s/n, Villanueva de la Cañada, 28692 Madrid, Spain
e-mail: mgiustini@cab.inta-csic.es
² Department of Physics and Astronomy, York University, 4700 Keele Street Toronto, ON M3J 1P3, Canada
³ Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4, Canada
⁴ Department of Physics and Astronomy, Cal Poly Humboldt, Arcata, CA 95521, USA
⁵ Physical Sciences Division, School of STEM, University of Washington Bothell, Bothell, WA 98011, USA
⁶ Department of Physics, Institute for Astrophysics and Computational Sciences, The Catholic University of America, Washington, DC 20064, USA
⁷ INAF, Osservatorio Astronomico di Brera, Via Bianchi 46, 23807 Merate (LC), Italy
⁸ INAF, Osservatorio di Astrofisica e Scienza dello Spazio di Bologna (OAS), via P. Gobetti 93/3, 40129 Bologna, Italy
⁹ Dipartimento di Fisica e Astronomia “Augusto Righi” (DIFA), Università degli Studi di Bologna, via P. Gobetti 93/2, 40129 Bologna, Italy
¹⁰ Dipartimento di Fisica, Università di Trento, Via Sommarive 14, Trento 38123, Italy
¹¹ Department of Astronomy & Astrophysics, Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA
¹² Institute for Gravitation and the Cosmos, Pennsylvania State University, University Park, PA 16802, USA
¹³ Department of Physics and Astronomy, College of Charleston, Charleston, SC 29424, USA
¹⁴ European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo s/n, Villanueva de la Cañada, 28692 Madrid, Spain
¹⁵ Department of Physics & Astronomy, University of Nevada, Las Vegas, 4505 S. Maryland Pkwy, Las Vegas, NV 89154-4002, USA
¹⁶ Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
¹⁷ Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse, 85748 Garching, Germany
¹⁸ Amsterdam UMC location University of Amsterdam, Biomedical Engineering and Physics, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
¹⁹ Informatics Institute, University of Amsterdam, Science Park 123, 1098 XG Amsterdam, The Netherlands

Received: 14 June 2022
Accepted: 31 May 2023

Abstract

Context. Accretion disk winds launched close to supermassive black holes (SMBHs) are a viable mechanism providing feedback between the SMBH and the host galaxy.

Aims. We aim to characterize the X-ray properties of the inner accretion disk wind of the nearby active galactic nucleus PG 1126-041 and to study its connection with the UV-absorbing wind.

Methods. We performed a spectroscopic analysis of eight XMM-Newton observations of PG 1126-041 taken between 2004 and 2015, using both phenomenological models and the most advanced accretion disk wind models available. For half of the data set, we were able to compare the X-ray analysis results with the results of quasi-simultaneous, high-resolution, spectroscopic UV observations taken with the Cosmic Origins Spectrograph on board the Hubble Space Telescope.

Results. The X-ray spectra of PG 1126-041 are complex and absorbed by ionized material, which is highly variable on multiple timescales, sometimes as short as 11 days. Accretion disk wind models can account for most of the X-ray spectral complexity of PG 1126-041, with the addition of massive clumps, represented by a partially covering absorber. Variations in column density (N_H ∼ 5 − 20 × 10²² cm⁻²) of the partially covering absorber drive the observed X-ray spectral variability of PG 1126-041. The absorption from the X-ray partially covering gas and from the blueshifted C IV troughs appear to vary in a coordinated way.

Conclusions. The line of sight toward PG 1126-041 offers a privileged view through a highly dynamic nuclear wind originating on inner accretion disk scales, making the source a very promising candidate for future detailed studies of the physics of accretion disk winds around SMBHs.