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arXiv · 2509.19666

A Bolometric Luminosity Correction Recipe for AGN at Any Epoch

Mojegan Azadi·Belinda Wilkes·Joanna Kuraszkiewicz·Steven. P. Willner·Matthew L. N. Ashby
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Abstract

Understanding how active galactic nuclei (AGN) affect their host galaxies requires determining their total radiative power across all wavelengths (i.e., bolometric luminosities). We show how AGN accretion disk spectral energy distribution (SED) templates, parameterized by supermassive black hole (SMBH) mass, Eddington ratio, spin, and inclination, can be used to estimate total radiated luminosities. Bolometric luminosities are calculated by integrating the accretion disk SEDs from 1$μ$m to 10keV over $0^\circ$--$90^\circ$ inclinations, ensuring consistent treatment of wavelength gaps, avoiding double-counting reprocessed emission, and accounting for anisotropy of visible--UV emission at different inclinations. The SED, and resulting bolometric corrections, depend strongly on SMBH mass and Eddington ratio, but only weakly on spin and inclination. Increasing SMBH mass produces cooler disks peaking at lower frequencies, whereas higher Eddington ratios (and spins) yield hotter disks peaking at higher frequencies. Larger inclinations suppress the visible--UV portion of the SED, whereas X-ray emission remains nearly isotropic. Bolometric corrections in the visible--NUV range (5100Å-3000Å) show strong dependence on SMBH mass, while X-ray bolometric corrections depend strongly on the Eddington ratio. Near the SED peak (FUV; $\sim$1450Å), parameter dependencies are weak, making this band particularly robust for estimating bolometric corrections. The X-ray band is reliable, though dependence on the Eddington ratio introduces a wide dynamic range. Because our SEDs are intrinsic and defined in the rest-frame, their application to Type 1 AGN is straightforward. For other AGN, however, corrections for obscuration by the host galaxy and torus are required in many cases.

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Mojegan Azadi, Belinda Wilkes, Joanna Kuraszkiewicz, Steven. P. Willner, Matthew L. N. Ashby. 2025-09-24. A Bolometric Luminosity Correction Recipe for AGN at Any Epoch. https://arxiv.org/abs/2509.19666

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