Adaptive optics imaging of Lyman break galaxies as progenitors of spheroids in the local Universe

In order to reveal the stellar mass distribution of z ∼ 3 galaxies, we are conducting deep imaging observations of U-dropout Lyman Break Galaxies (LBGs) with Adaptive Optics (AO) systems in K-band, which corresponds to rest-frame V-band of z ∼ 3 galaxies. The results of the Subaru intensive-program observations with AO36/NGS/IRCS indicate that 1) the K-band peaks of some of the LBGs brighter than K = 22.0 mag show significant offset from those in the optical images, 2) the z ∼ 3 $M$ LBGs and serendipitously observed Distant Red Galaxies (DRGs) have flat profiles similar to disk galaxies in the local universe (i.e., Srsic with n < 2), and 3) the surface stellar mass densities of the $M$ LBGs are 3-6 times larger than those of disk galaxies at z = 0 1. Considering the lack of n > 2 systems among the luminous z ∼ 3 LBGs and DRGs, and their strong spatial clustering, we infer that the dense n < 2 disk-like structures evolve into the n > 2 spheroids of nearby galaxies through relaxations due to major merger events.