Supermassive Black Hole Winds in X-rays: SUBWAYS
Résumé
We present a new X-ray spectroscopic study of 22 luminous (2 × 10 45 ≲ L bol /erg s −1 ≲ 2 × 10 46 ) 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 H α and Fe XXVI Ly α ) 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 (≳0.1 c ) 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.
Domaines
Planète et Univers [physics]Origine | Fichiers éditeurs autorisés sur une archive ouverte |
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