By  Y. Xu

Through flux- and time-resolved high-resolution X-ray spectroscopy of archival XMM-Newton observations on six highly accreting narrow-line Seyfert 1 (NLS1) AGN, we have identified three new ultra-fast outflows (UFOs) and uncovered multiphase wind structures in five of these AGN. Our findings suggest that UFOs are driven by radiation pressure in high-Eddington AGN, with tentative evidence pointing to a decreasing radiative acceleration as the Eddington ratio increases. NewAthena/X-IFU simulations of UFOs demonstrate that this instrument will enable precise tracking of UFO evolution across varying flux states. This will provide critical insights into their location, launching mechanisms, and energetics. With NewAthena, the enigmatic nature of UFOs can be fully revealed, marking a significant leap forward in understanding AGN feedback processes.

Access to the manuscript in ADS.