Ruling Out Compact Jets as the Dominant Source of Radio Emission in Radio-quiet, High-Eddington-ratio Active Galactic Nuclei

Abstract The origin of core radio emission in radio-quiet active galactic nuclei (AGNs) is still actively debated. General-relativistic magnetohydrodynamics simulations often predict the launching of moderately large-scale jets from super-Eddington accretion flows, but this prediction seems at odds with observations indicating most high/super-Eddington AGNs appear radio-quiet. Here, we use the ratio of radio to X-ray luminosities as a multiwavelength diagnostic to probe the origin of radio emission in a sample of 69 radio-quiet, high/super-Eddington AGNs with black hole masses M BH ∼ 10 5 –10 9 M ⊙ . With this wide dynamic range in M BH , we adapt existing formalisms for how jetted radio emission and accretion-powered X-ray emission scale with black hole mass into the super-Eddington regime. We find that the radio/X-ray luminosity ratios observed across this M BH range are inconsistent with a jet-dominated model for radio emission. We discuss how our results may instead be consistent with a corona-dominated radio emission origin with a contribution from outflows at higher accretion rates.