Program: GN-2025A-Q-306

Dual AGNs are predicted to be a critical stage of galaxy merger-driven supermassive black hole growth. Prior attempts to select dual AGNs have focused predominantly on optical spectroscopic selection and late-stage galaxy mergers. Here we propose a Gemini GMOS 2025a science program to study the optical spectroscopic properties of 26 spatially resolved mid-IR dual AGNs in earlier-stage galaxy mergers, with a total program request of ~25.5 hours (~3.2 nights). These mid-IR dual AGNs were systematically selected using the Wide-Field Infrared Survey Explorer (WISE) and optical imaging from the Dark Energy Camera Legacy Survey. This will be the first sample of spatially resolved WISE mid-IR dual AGNs followed-up in the optical, providing the first investigation into the occupation fraction of Type 1 and Type 2 AGNs in mid-IR selected dual AGNs. Using Gemini GMOS, we will (1) determine the spectroscopic redshift for each optical nucleus, (2) estimate the optical emission line flux ratios to constrain the optical types, and (3) study the multiwavelength AGN selection function and multiwavelength properties of this sample as a function of pair separation, merger mass ratio, and host merger stage. This Gemini GMOS program will directly support a Chandra program and will be supplemented by a UKIRT back-up near-IR imaging program.