Chasing the Light: Shadowing, Collimation, and the Super-Eddington Growth of Infant Black Holes in JWST-Discovered AGNs (2501.09854v1)

Abstract: Observations with the James Webb Space Telescope (JWST) have uncovered a substantial population of high-redshift broad-line active galactic nuclei (AGNs) characterized by moderate luminosities, weak X-ray emissions, and faint high-ionization lines, challenging conventional models of black hole growth and AGN activity. In this study, we propose that these sources are accreting at super-Eddington rates and use geometrically thick, non-advective disk models to investigate the critical roles of photon scattering, reflections, and shadowing within funnel-like structures along the disk's rotation axis. Our models predict highly collimated radiation fields, with isotropic-equivalent luminosities vastly exceeding the Eddington limit in polar directions, and significant suppression of emission at higher inclination angles due to shadowing. These effects result in altered spectral energy distributions and pronounced anisotropies in observable properties. Key features include ultra-blue UV continuum slopes (alpha=+0.5 to +0.8), bolometric correction factors varying by over an order of magnitude with orientation, and suppressed coronal X-ray emissions. The anisotropy and shadowing effects may also explain the observed faintness of broad high-ionization emission lines, as the viewing angle strongly modulates both continuum brightness and the illumination of the broad-line region. These findings indicate that super-Eddington accretion flows, shaped by thick disk geometries and anisotropic radiation fields, can naturally account for many puzzling features of JWST-discovered AGNs and provide new insights into black hole growth in the early universe.