Wind-luminosity evolution in NLS1 AGN 1H 0707-495

TL;DR

This study investigates the wind and outflow properties in the highly accreting NLS1 AGN 1H 0707-495 using flux-resolved X-ray spectroscopy, revealing anti-correlations between wind velocity and luminosity and suggesting a multi-phase outflow structure.

Contribution

It provides new insights into the wind structure and variability in 1H 0707-495, highlighting differences from similar sources and proposing a scenario involving radiation-driven wind launch radius expansion.

Findings

Wind spectral lines weaken at higher luminosities due to increased ionization.

Wind velocity is anticorrelated with luminosity, opposite to other NLS1s.

Detection of emission lines suggests a larger wind opening angle.

Abstract

Ultra-fast outflows (UFOs) have been detected in the high-quality X-ray spectra of a number of active galactic nuclei (AGN) with fairly high accretion rates and are thought to significantly contribute to the AGN feedback. After a decade of dedicated study, their launching mechanisms and structure are still not well understood, but variability techniques may provide useful constraints. In this work, therefore, we perform a flux-resolved X-ray spectroscopy on a highly accreting and variable NLS1 AGN, 1H 0707-495, using all archival XMM-Newton observations to study the structure of the UFO. We find that the wind spectral lines weaken at higher luminosities, most likely due to an increasing ionization parameter as previously found in a few similar sources. Instead, the velocity is anticorrelated with the luminosity, which is opposite to the trend observed in the NLS1 IRAS 13224-3809. Furthermore, the detection of the emission lines, which are not observed in IRAS 13224-3809, indicates a wind with a larger opening angle in 1H 0707-495, presumably due to a higher accretion rate. The emitting gas is found to remain broadly constant with the luminosity. We describe the variability of the wind with a scenario where the strong radiation extends the launch radius outwards and shields the outer emitting gas, similarly to super-Eddington compact objects, although other possible explanations are discussed. Our work provides several hints for a multi-phase outflow in 1H 0707-495.