Abstract:
One of the critical but outstanding issues is if structural growth of star-forming galaxies can differ depending on their surrounding environments. We conducted the Adaptive Optics (AO)-assisted imaging observations for star-forming galaxies in a dense proto-cluster core at z = 2.53 with Subaru/IRCS+AO188. A combination of AO and narrow-band filter allows us to obtain the maps of Ha-emitting region, i.e., star-forming region, with an angular resolution of 0.1-0.2 arcsec. Based on the stacking analyses, we investigated the relative distribution of the star-forming region to the underlying stellar component. We find that the star-forming region is further extended than the stellar component for the massive star-forming galaxies, suggesting the inside-out growth of the structure. Our group has found a similar trend for star-forming galaxies at z~2 in general fields with the same observational technique. Our results suggest that the internal secular processes mainly contribute to the structural evolution of star-forming galaxies at z=2-2.5 irrespective of surrounding environments.