Tell-tale Spectral Signatures of MHD-driven Ultrafast Outflows in AGNs
Abstract
We aim to explore spectral signatures of the predicted multi-ion ultrafast outflows (UFOs) in the broadband X-ray spectra of active galactic nuclei by exploiting an accretion disk-wind model in the context of a simple magnetohydrodynamic (MHD) framework. We are focused primarily on examining the spectral dependences on a number of key properties: (1) ionizing luminosity ratio λ ion, (2) line-of-sight wind density slope p, (3) optical/UV-to-X-ray strength α OX, (4) inclination θ, (5) X-ray photon index Γ, and (6) wind density factor f D . With an emphasis on radio-quiet Seyferts in the sub-Eddington regime, multi-ion UFO spectra are systematically calculated as a function of these parameters to show that MHD-driven UFOs imprint a unique asymmetric absorption line profile with a pronounced blue tail structure on average. Such a characteristic line signature is generic to the simplified MHD disk-wind models presented in this work due to their specific kinematics and density structure. The properties of these absorption line profiles could be utilized as a diagnostics to distinguish between different wind-driving mechanisms or even the specific values of given MHD wind parameters. We also present high-fidelity microcalorimeter simulations in anticipation of the upcoming XRISM/Resolve and Athena/X-IFU instruments to demonstrate that such a "tell-tale" sign may be immune to a spectral contamination by the presence of additional warm absorbers and partially covering gas.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 2022
- DOI:
- arXiv:
- arXiv:2205.08894
- Bibcode:
- 2022ApJ...940....6F
- Keywords:
-
- Black hole physics;
- X-ray active galactic nuclei;
- Quasar absorption line spectroscopy;
- Radiative magnetohydrodynamics;
- Galaxy accretion disks;
- Spectroscopy;
- Plasma astrophysics;
- 159;
- 2035;
- 1317;
- 2009;
- 562;
- 1558;
- 1261;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- accepted to ApJ