Supermassive Black Hole Winds in X-rays: SUBWAYS

I. Ultra-fast outflows in quasars beyond the local Universe

¹ Department of Physics and Astronomy (DIFA), University of Bologna, Via Gobetti, 93/2, 40129 Bologna, Italy
e-mail: gabriele.matzeu@unibo.it
² INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Gobetti, 93/3, 40129 Bologna, Italy
³ European Space Agency (ESA), European Space Astronomy Centre (ESAC), 28691 Villanueva de la Cañada, Madrid, Spain
⁴ Dipartimento di Matematica e Fisica, Universitá degli Studi Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
⁵ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
⁶ INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy
⁷ Department of Physics and Astronomy, College of Charleston, Charleston, SC 29424, USA
⁸ Space Science Data Center – ASI, Via del Politecnico s.n.c., 00133 Roma, Italy
⁹ INAF – Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone (Roma), Italy
¹⁰ Univ. Grenoble Alpes, CNRS, IPAG, 621 Av. Centrale, 38400 Saint-Martin-d’Hères, France
¹¹ Instituto de Astronomía, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Ciudad de México 04510, México
¹² Department of Physics, University of Rome ‘Tor Vergata’, Via della Ricerca Scientifica 1, 00133 Rome, Italy
¹³ Department of Astronomy, University of Maryland, College Park, MD 20742, USA
¹⁴ NASA/Goddard Space Flight Center, Code 662, Greenbelt, MD 20771, USA
¹⁵ INAF – Istituto di Astrofisica e Planetologia Spaziali, Via Fosso del Cavaliere, 00133 Roma, Italy
¹⁶ Centro de Astrobiología (CSIC-INTA), Camino Bajo del Castillo s/n, Villanueva de la Cañada, 28692 Madrid, Spain
¹⁷ Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544-1001, USA
¹⁸ Physics Department, The Technion, 32000 Haifa, Israel
¹⁹ INAF – Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, 34143 Trieste, Italy
²⁰ Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA
²¹ Center for Cosmology and Astroparticle Physics, 191 West Woodruff Avenue, Columbus, OH 43210, USA
²² SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
²³ Departament de Física, EEBE, Universitat Politècnica de Catalunya, Av. Eduard Maristany 16, 08019 Barcelona, Spain
²⁴ ESA – European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands
²⁵ Leiden Observatory, PO Box 9513 2300 RA Leiden, The Netherlands
²⁶ Department of Physics, Institute for Astrophysics and Computational Sciences, The Catholic University of America, Washington, DC 20064, USA
²⁷ Dipartimento di Fisica e Astronomia, Università di Firenze, via G. Sansone 1, 50019 Sesto Fiorentino, Firenze, Italy
²⁸ INAF – Osservatorio Astronomico di Brera, Via Bianchi 46, 23807 Merate (LC), Italy
²⁹ Department of Physics & Astronomy, University of Nevada, Las Vegas, USA
³⁰ Department of Physics & Astronomy, University of Leicester, Leicester LE1 7RH, UK
³¹ Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
³² Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge CB3 0HE, UK
³³ Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße 1, 85748 Garching bei München, Germany

Received: 21 September 2022
Accepted: 5 December 2022

Abstract

We present a new X-ray spectroscopic study of 22 luminous (2 × 10⁴⁵ ≲ L_bol/erg s⁻¹ ≲ 2 × 10⁴⁶) active galactic nuclei (AGNs) at intermediate redshifts (0.1 ≲ z ≲ 0.4), as part of the SUpermassive Black hole Winds in the x-rAYS (SUBWAYS) sample, mostly composed of quasars and type 1 AGNs. Here, 17 targets were observed with XMM-Newton in 2019–2020, and the remaining 5 are from previous observations. The aim of this large campaign (1.45 Ms duration) is to characterise the various manifestations of winds in the X-rays driven from supermassive black holes in AGNs. In this paper we focus on the search for and characterisation of ultra-fast outflows (UFOs), which are typically detected through blueshifted absorption troughs in the Fe K band (E > 7 keV). By following Monte Carlo procedures, we confirm the detection of absorption lines corresponding to highly ionised iron (e.g. Fe XXV Hα and Fe XXVI Lyα) in 7 out of 22 sources at the ≳95% confidence level (for each individual line). The global combined probability of such absorption features in the sample is > 99.9%. The SUBWAYS campaign, based on XMM-Newton, extends to higher luminosities and redshifts than previous local studies on Seyferts. We find a UFO detection fraction of ∼30% of the total sample, which is in agreement with previous findings. This work independently provides further support for the existence of highly ionised matter propagating at mildly relativistic speeds (≳0.1c) in a considerable fraction of AGNs over a broad range of luminosities, which is believed to play a key role in the self-regulated AGN feeding-feedback cycle, as also supported by hydrodynamical multi-phase simulations.