Relativistic Outflows Power a Quasi-periodic Eruption: Constraints on Energetics, Mass Loss, and Emission Mechanisms
Year: 2026
Type: article
Abstract: Quasi-periodic eruptions (QPEs) are recurring bursts of X-ray radiation originating from supermassive black holes (SMBHs). They are an unprecedented type of structured, high-amplitude SMBH variability, but the physical origins of their regularity, timescales, energetics, and emission are uncertain. We present new XMM-Newton observations of the QPEs in ZTF 19acnskyy/“Ansky,” constituting the deepest observations of individual bursts in any source thus far. The X-ray spectra reveal time-evolving P Cygni profiles comprising blueshifted absorption and redshifted emission from L-shell transitions of Fe xix – xxiv , with column densities N H ∼ 10 22−23 cm −2 and bulk velocities of ∣ v w / c ∣ ∼ 0.2, indicating relativistic mass ejections during each eruption. We construct a time-dependent analytical model of a wind turning on to self-consistently compute its evolving luminosity and ionization properties, and find that the light curve and spectral lines can be simultaneously produced by a wide-angle outflow with M ̇ ∼ 1 0 − 9 – 1 0 − 8 M ⊙ s − 1 kinetically powering the X-rays with an efficiency of L X / E ̇ K ∼ 0.1 . For a covering fraction f Ω ∼ 0.5, each eruption ejects ∼10 −3 M ⊙ and ≳10 49 erg of kinetic energy, setting an upper bound on the QPE lifetime of ≲1000 bursts if the underlying mass reservoir is ∼1 M ⊙ , and implying that the bursts may result in detectable multiwavelength signatures of reverberation and feedback. These measurements provide new quantitative constraints on QPE energetics, emission mechanisms, and the mass/energy they recycle into their circumnuclear environments, as well as an observational probe for direct comparison with physical models and hydrodynamical simulations of QPEs.
Authors: Joheen Chakraborty, Erin Kara, Wenbin Lu, Brian D. Metzger, Peter Kosec, Riccardo Arcodia, Itai Linial, Olivia Aspegren, Ehud Behar, Sudip Bhattacharyya, Margherita Giustini, Lorena Hernández-García, Daniel Kasen, Giovanni Miniutti, Frits Paerels, Erwan Quintin, Claudio Ricci, Daniele Rogantini, Paula Sánchez-Sáez, Fatima Zaidouni
Institutions: University of California System, Flatiron Institute, Columbia University, Center for Astrophysics Harvard & Smithsonian, Harvard University, New York University, Tata Institute of Fundamental Research, Centro de Astrobiología, Universidad Diego Portales, Lawrence Berkeley National Laboratory, European Space Agency, University of Geneva, University of Chicago, European Southern Observatory, European Southern Observatory
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,400
OpenAlex ID: W7204972605