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Arxiv: Chasing the Light: Shadowing, Collimation, and the Super-Eddington Growth of Infant Black Holes in JWST-Discovered AGNs Published: 1/16/2025 11:50:41 PM Updated: 1/16/2025 11:50:41 PM

Paper abstract: Observations with the James Webb Space Telescope (JWST) have uncovered asubstantial population of high-redshift broad-line active galactic nuclei(AGNs) characterized by moderate luminosities, weak X-ray emissions, and fainthigh-ionization lines, challenging conventional models of black hole growth andAGN activity. In this study, we propose that these sources are accreting atsuper-Eddington rates and use geometrically thick, non-advective disk models toinvestigate the critical roles of photon scattering, reflections, and shadowingwithin funnel-like structures along the disk's rotation axis. Our modelspredict highly collimated radiation fields, with isotropic-equivalentluminosities vastly exceeding the Eddington limit in polar directions, andsignificant suppression of emission at higher inclination angles due toshadowing. These effects result in altered spectral energy distributions andpronounced anisotropies in observable properties. Key features includeultra-blue UV continuum slopes (alpha=+0.5 to +0.8), bolometric correctionfactors varying by over an order of magnitude with orientation, and suppressedcoronal X-ray emissions. The anisotropy and shadowing effects may also explainthe observed faintness of broad high-ionization emission lines, as the viewingangle strongly modulates both continuum brightness and the illumination of thebroad-line region. These findings indicate that super-Eddington accretionflows, shaped by thick disk geometries and anisotropic radiation fields, cannaturally account for many puzzling features of JWST-discovered AGNs andprovide new insights into black hole growth in the early universe.