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arXiv · 2304.06065

The Most Obscured AGNs in the XMM-SERVS Fields

Wei Yan·W. N. Brandt·Fan Zou·Shifu Zhu·Chien-Ting J. Chen·Ryan C. Hickox·Bin Luo·Qingling Ni·David M. Alexander·Franz E. Bauer·Cristian Vignali·Fabio Vito
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Abstract

We perform X-ray spectral analyses to derive characteristics (e.g., column density, X-ray luminosity) of $\approx$10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey (XMM-SERVS), which was designed to investigate the growth of supermassive black holes across a wide dynamic range of cosmic environments. Using physical torus models (e.g., Borus02) and a Bayesian approach, we uncover 22 representative Compton-thick (CT; $N_{\rm H} \;>\; 1.5\times10^{24}\; \rm cm^{-2}$) AGN candidates with good signal-to-noise ratios as well as a large sample of 136 heavily obscured AGNs. We also find an increasing CT fraction (\fct ) from low ($z<0.75$) to high ($z>0.75$) redshift. Our CT candidates tend to show hard X-ray spectral shapes and dust extinction in their SED fits, which may shed light on the connection between AGN obscuration and host-galaxy evolution.

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Wei Yan, W. N. Brandt, Fan Zou, Shifu Zhu, Chien-Ting J. Chen, Ryan C. Hickox, Bin Luo, Qingling Ni, David M. Alexander, Franz E. Bauer, Cristian Vignali, Fabio Vito. 2023-04-12. The Most Obscured AGNs in the XMM-SERVS Fields. https://doi.org/10.3847/1538-4357%2Faccea6

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