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arXiv · 2507.01293

The Evolutionary Pathway of Low-mass Supermassive Black Holes at Intermediate Redshift: Insights from the JADES Survey

Atsushi Hoshi·Toru Yamada
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Abstract

Understanding the relationship between supermassive black holes (SMBHs) and their host galaxies at different redshifts is crucial for unraveling the processes of SMBH-galaxy co-evolution. We present the properties of nine type 1 Active Galactic Nuclei (AGNs) at intermediate redshift ($2 4$ ($1-10\%$), suggesting that black holes and galaxies may trace different evolutionary pathways at intermediate and high redshift. We also perform 2D image decomposition using GALFIT to constrain the bulge mass by evaluating the bulge contribution in the rest-frame near-infrared flux. We identify the AGNs with low BH-to-bulge mass ratios compared to those observed in the nearby bulge-dominant galaxies. This finding suggests the existence of a galaxy-first evolutionary path, in which bulge formation occurs before substantial gas is efficiently accreted onto the central engine.

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Atsushi Hoshi, Toru Yamada. 2025-07-02. The Evolutionary Pathway of Low-mass Supermassive Black Holes at Intermediate Redshift: Insights from the JADES Survey. https://arxiv.org/abs/2507.01293

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