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Abstract

The role of active galactic nuclei (AGN) in regulating galaxy evolution is widely accepted as a feedback process suppressing star formation. However, observational evidence for it remains controversial. This thesis examines ionized gas outflows across and beyond AGN populations, utilizing SDSS-IV MaNGA’s spatially resolved spectroscopy together with multi-wavelength AGN selection. We demonstrate that radio and optical diagnostics identify distinct AGN populations. Radio-selected AGN exhibit broader emission lines reaching larger radii, suggesting evolved or longer-lasting feedback. Furthermore, when radio and optical AGN signatures are simultaneously present, feedback appears maximized, hinting at combined radiative and kinetic modes. Since radio signatures appear to hint at long-lasting AGN signatures, we investigate galaxies lacking ongoing AGN. Strikingly, radio-detected galaxies without current AGN exhibit broader emission linewidths than those without radio. These show outflow-like kinematics and share global properties (e.g., radio compactness and redder colors) with radio-detected AGN. This alignment suggests shared physical origins, likely connecting past AGN activity. Pointing to feedback that persists beyond the AGN’s observable phase, these systems are strong fossil-outflow candidates. This thesis presents a time-dependent view of AGN feedback, laying the foundation for future studies that connect AGN duty cycles, multiwavelength selection, and spatially resolved diagnostics.