1. X-Ray Winds in Nearby-to-distant Galaxies (X-WING). I. Legacy Surveys of Galaxies with Ultrafast Outflows and Warm Absorbers in z ∼ 0–4
- Author
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Satoshi Yamada, Taiki Kawamuro, Misaki Mizumoto, Claudio Ricci, Shoji Ogawa, Hirofumi Noda, Yoshihiro Ueda, Teruaki Enoto, Mitsuru Kokubo, Takeo Minezaki, Hiroaki Sameshima, Takashi Horiuchi, and Shoichiro Mizukoshi
- Subjects
Black hole physics ,Active galactic nuclei ,X-ray active galactic nuclei ,Supermassive black holes ,Observational astronomy ,Astrophysics ,QB460-466 - Abstract
As an inaugural investigation under the X-ray Winds In Nearby-to-distant Galaxies (X-WING) program, we assembled a data set comprising 132 active galactic nuclei (AGNs) spanning redshifts z ∼ 0–4 characterized by blueshifted absorption lines indicative of X-ray winds. Through an exhaustive review of previous research, we compiled the outflow parameters for 583 X-ray winds, encompassing key attributes such as outflow velocities ( V _out ), ionization parameters ( ξ ), and hydrogen column densities. By leveraging the parameters V _out and ξ , we systematically categorized the winds into three distinct groups: ultrafast outflows (UFOs), low-ionization parameter (low-IP) UFOs, and warm absorbers (WAs). Strikingly, a discernible absence of linear correlations in the outflow parameters, coupled with distributions approaching instrumental detection limits, was observed. Another notable finding was the identification of a velocity gap around V _out ∼ 10,000 km s ^−1 . This gap was particularly evident in the winds detected via absorption lines within the ≲2 keV band, indicating disparate origins for low-IP UFOs and WAs. In cases involving Fe xxv /Fe xxvi lines, where the gap might be attributed to potential confusion between emission/absorption lines and the Fe K-edge, the possibility of UFOs and galactic-scale WAs being disconnected is considered. An examination of the outflow and dust sublimation radii revealed a distinction: UFOs appear to consist of dust-free material, whereas WAs likely comprise dusty gas. From 2024, the X-Ray Imaging and Spectroscopy Mission is poised to alleviate observational biases, providing insights into the authenticity of the identified gap, a pivotal question in comprehending AGN feedback from UFOs.
- Published
- 2024
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