2025/03/31 by Sergei Dyda, Dyda, Sergei, Randall Dannen +7 · 1 citation
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #Pulsars and Gravitational Waves Research
paper · pdf · doi:10.48550/arxiv.2504.00117
openalex publication_date 2025/03/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We use a combination of radiation hydrodynamics (rad-HD) and photoionization modeling to study line-driven disc winds for a range of black hole masses. We refined previous models by incorporating heating, cooling, and radiation forces from spectral lines calculated using a photoionization code, assuming that composite AGN spectra irradiate the gas. For black holes with masses 3 × 106 \lesssim \rm MBH/M\odot \lesssim 108, the mass loss rate, \rm Mw increases proportionally with the disk Eddington fraction, Γ. The insensitivity of \rm Mw to the hardness of the spectral energy distribution (SED) arises because the central region is dominated by radiation in the frequency range with ample spectral lines for the range of MBH considered here. Disc winds are suppressed or fail outside the above mass range because of a dearth of line-driving photons. We find stronger winds, both in terms of \rm Mw and wind velocity compared to previous disc wind models. Our winds are stronger because of an enhanced line force from including many spectral lines in the X-ray band. These lines were unavailable and, hence, unaccounted for in previous photoionization studies and their subsequent application to AGN wind models. For Γ\gtrsim 0.4, \rm Mw is higher than the assumed disc accretion rate, implying that the wind feeds back strongly. Our findings indicate the necessity of utilizing comprehensive and current atomic data along with a more thorough approach to radiation transfer - both spatially and temporally - to accurately calculate the line force.