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arXiv · 2607.02666

The MIRI Early Obscured-AGN Wide Survey (MEOW): A Population of Hidden AGN at $z \gtrsim 5$ Revealed by JWST/MIRI Imaging

Abstract

We present the MIRI Early Obscured-AGN Wide Survey (MEOW), a JWST/MIRI imaging survey designed to detect dust-obscured active galactic nuclei (AGN) across cosmic time, with a particular focus on the high-redshift universe at $z \gtrsim 5$. MEOW observes the GOODS-N and GOODS-S fields with 43 pointings covering 95 arcmin$^2$ with the F1000W and F2100W filters, reaching depths of 0.5 and 3.6 $\mu$Jy ($5\sigma$), respectively. Using spectral energy distribution (SED) modeling combining MEOW photometry with archival HST, JWST/NIRCam, and SCUBA-2 data, we identify a sample of 16 MIRI-selected AGN at $z = 4.5$--$7.2$ (12 spectroscopically confirmed), spanning bolometric luminosities of $L_{\rm bol} = 10^{44.6}$--$10^{46.4}$~erg~s$^{-1}$. Twelve of the 16 AGN are newly identified in this work, including at least five narrow-line AGN representing the obscured population to which broad-line spectroscopic searches are insensitive. Two broad-line AGN exhibit markedly different mid-infrared emission properties, consistent with one being a little red dot (LRD) and the other either a typical AGN or an LRD with unusually strong hot-dust emission. The MIRI-selected AGN bolometric luminosity function at $z = 4.5$--$6$ yields number densities comparable to those of broad-line AGN and LRDs, suggesting that obscured AGN contribute significantly to the total AGN census at these epochs. The narrow-line AGN reside in diverse host environments, with evidence for both circumnuclear and host-galaxy-scale obscuration, pointing to multiple physical mechanisms at work. These results establish JWST/MIRI imaging as an indispensable component of a multi-faceted approach to a complete census of early supermassive black hole growth.

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BibTeXRIS

Gene C. K. Leung, Anna-Christina Eilers, Ryan Endsley, Steven L. Finkelstein, Micaela B. Bagley, Guillermo Barro, Anton M. Koekemoer, Pablo G. Pérez-González, Nor Pirzkal, Bren E. Backhaus, Teodora-Elena Bulichi, Jaclyn B. Champagne, Katherine Chworowsky, Nikko J. Cleri, Mark Dickinson, Xiaohui Fan, Seiji Fujimoto, Norman A. Grogin, Allison Kirkpatrick, Dale D. Kocevski, Vasily Kokorev, Rebecca L. Larson, Ray A. Lucas, Fabio Pacucci, Casey Papovich, Anthony J. Taylor, Natalia C. Villanueva, Guang Yang. 2026-07-02. The MIRI Early Obscured-AGN Wide Survey (MEOW): A Population of Hidden AGN at $z \gtrsim 5$ Revealed by JWST/MIRI Imaging. https://arxiv.org/abs/2607.02666

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