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arXiv · 2510.16249

Accretion and Jet Coupling in Powerful Radio Quasars at Cosmic Noon

Abstract

We present bolometric corrections, as a function of wavelength, for powerful radio-loud quasars from the Revised Third Cambridge Catalogue of Radio Galaxies (3CRR) at 1 < z < 2. The bolometric luminosities are derived by integrating the intrinsic accretion disk spectral energy distributions (SEDs) over the range 1{\mu}m-10keV (excluding reprocessed infrared emission) and integrating over inclination angles (to account for accretion disk emission anisotropy). We use accretion disk models, fitted to observed data, to self-consistently bridge the unobserved wavelength region between the UV and X-rays with no need for far-UV gap repair. The resulting bolometric corrections span a wide range (~1-400) across different wavelengths, showing minimal dependence on redshift, X-ray luminosity, and black hole mass, which is possibly due to a narrow range of these intrinsic AGN parameters in the sample. However, when the sample is divided by Eddington ratio, the X-ray bolometric corrections exhibit distinctly different values, with higher correction factors corresponding to higher Eddington ratios. We also examine the connection between total radio luminosity and accretion disk power. For most 3CRR sources, the radio power constitutes roughly 1%-10% of the accretion disk luminosity. However, quasars with compact jets exhibit higher radio luminosities for a given accretion disk power. This suggests a higher efficiency of conversion of accretion power to radio luminosity in the younger jets. Our results provide physically motivated bolometric corrections for powerful radio quasars that are applicable to powerful radio-loud quasars at any epoch.

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BibTeXRIS

Mojegan Azadi, Belinda Wilkes, Joanna Kuraszkiewicz, Steven. P. Willner, Matthew L. N. Ashby. 2025-10-17. Accretion and Jet Coupling in Powerful Radio Quasars at Cosmic Noon. https://arxiv.org/abs/2510.16249

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