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arXiv · 2506.02124

The Relationship Between Eddington Ratio and Column Density in U/LIRG AGN

Jaya Nagarajan-Swenson·George C. Privon·Aaron S. Evans·Loreto Barcos-Muñoz·Claudio Ricci·Anne M. Medling·Vivian U·Alejandro Saravia·Kara N. Green·Makoto Johnstone·Gabriela A. Meza
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Abstract

The local X-ray AGN population appears to follow a growth cycle regulated by the AGN's own radiation, marked by changes in their obscuration and Eddington ratio during accretion events. Because AGN in infrared-selected galaxies are more likely to be Compton-thick and have evidence for over-massive black holes, we explore whether infrared-selected AGN follow the radiation-regulated AGN growth scheme. We calculate the Eddington ratios of nine U/LIRG AGN with dynamical BH mass measurements, finding that though the number of objects is limited, AGN in IR-selected galaxies appear consistent with radiation pressure-regulated growth. We suggest that enlarging the sample of dynamical BH mass measurements in IR-selected systems will provide more stringent tests of whether their AGN are primarily regulated by radiation pressure.

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Jaya Nagarajan-Swenson, George C. Privon, Aaron S. Evans, Loreto Barcos-Muñoz, Claudio Ricci, Anne M. Medling, Vivian U, Alejandro Saravia, Kara N. Green, Makoto Johnstone, Gabriela A. Meza. 2025-06-02. The Relationship Between Eddington Ratio and Column Density in U/LIRG AGN. https://doi.org/10.3847/2515-5172%2Fadddc0

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