Daryl Joe D. Santos (NTHU), Tomotsugu Goto (NTHU), Seong Jin Kim (NTHU), and the AKARI NEP Collaboration
Galaxy environment has shown to affect various intrinsic galaxy properties, suggesting its important role in galaxy formation and evolution. However, previous observations in the optical and ultraviolet wavelengths missed dusty star-forming galaxies (SFGs) and active galactic nuclei (AGNs). The aim of this work is to give a complete picture of this issue by studying the role of galaxy environment in the properties of galaxies detected in the mid-infrared (MIR) wavelengths, where these previously missed dusty objects can be observed, by the AKARI IR telescope in the North Ecliptic Pole Wide (NEPW) field at 0 < z < 1.2. We take advantage of AKARI’s continuous 9-band filter system which gives us better diagnostics compared with other infrared (IR) telescopes (i.e., WISE and Spitzer) in identifying SFGs and AGNs which are both bright in the IR wavelengths. We chose local density as the environmental measure for this study. We measured the local densities of galaxies detected by the Subaru/HSC telescope and used CIGALE SED fitting to constrain the galaxy properties of our MIR galaxies. We report on our MIR galaxies’ observed relationships between galaxy environments and various properties (e.g., color, luminosity, star-formation rate, etc) as well as their correlation with our previous results related to AGN activity.