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arXiv · 2309.16528

A new discovery space opened by eROSITA: Ionised AGN outflows from X-ray selected samples

Abstract

In the context of an evolutionary model, the outflow phase of an Active Galactic Nuclei (AGN) occurs at the peak of its activity, once the central SMBH is massive enough to generate sufficient power to counterbalance the potential well of the host galaxy. This phase plays a vital role in galaxy evolution. We aim to apply various selection methods to isolate powerful AGNs in the feedback phase, trace and characterise their outflows, and explore the link between AGN luminosity and outflow properties. We applied a combination of methods to the eROSITA Final Equatorial Depth survey (eFEDS) catalogue and isolated ~1400 candidates at z>0.5 out of ~11750 AGNs (~12\%). We tested the robustness of our selection on the small subsample of 50 sources with available good quality SDSS spectra at 0.5 1\%. We find that the majority of the outflows have momentum flux ratios lower than 20 which rules out an energy-conserving nature. Our present work points to the unequivocal existence of a rather short AGN outflow phase, paving the way towards a new avenue to dissect AGN outflows in large samples within eROSITA and beyond.

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Blessing Musiimenta, Marcella Brusa, Teng Liu, Mara Salvato, Johannes Buchner, Zsofi Igo, Sophia G. H. Waddell, Yoshiki Toba, Riccardo Arcodia, Johan Comparat, David M. Alexander, Francesco Shankar, Andrea Lapi, Cristina Ramos Almeida, Antonis Georgakakis, Andrea Merloni, Tanya Urrutia, Junyao Li, Yuichi Terashima, Yue Shen, Qiaoya Wu, Tom Dwelly, Kirpal Nandra, Julien Wolf. 2023-09-28. A new discovery space opened by eROSITA: Ionised AGN outflows from X-ray selected samples. https://doi.org/10.1051/0004-6361%2F202245555

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