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arXiv · 2510.11010

The Relation Between AGN and Host Galaxy Properties in the JWST Era: II. The merger-driven evolution of Seyferts at Cosmic Noon

Nina Bonaventura·Jianwei Lyu·George H. Rieke·Andrew J. Bunker·Chris J. Willott·Christopher N. A. Willmer
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Abstract

In Paper I, we exploited the unsurpassed resolution and depth of JWST/NIRCam imagery to investigate the relationship between AGN and host-galaxy properties in the JWST era, finding a correlation between the level of spatial disturbance (as measured by shape asymmetry, $A_S$) and obscuration ($N_H$). Here in Paper II, we report an expansion of our X-ray and infrared analysis of Seyfert-luminosity host galaxies with four additional metrics to the single-metric morphology analysis of Paper I, as well as new samples of inactive control galaxies. This expanded study of one of the largest and most complete, multi-wavelength samples of AGN detected at $0.6<z<2.4$ in the GOODS-South and North fields, confirms that mergers surprisingly play a significant role in obscured, sub-quasar AGN host galaxies. Additionally, the pattern of morphological disturbances observed amongst the X-ray- and mid-IR-selected AGN suggests that these represent different phases of AGN evolution tied to a major-merger timeline, as opposed to distinct populations of AGN. These results indicate that mergers are important in triggering sub-quasar AGN at these redshifts.

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Nina Bonaventura, Jianwei Lyu, George H. Rieke, Andrew J. Bunker, Chris J. Willott, Christopher N. A. Willmer. 2025-10-13. The Relation Between AGN and Host Galaxy Properties in the JWST Era: II. The merger-driven evolution of Seyferts at Cosmic Noon. https://arxiv.org/abs/2510.11010

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