Poster Presentation

How do galaxy mergers affect the ionized gas kinematics of galaxies? ~KOOLS-IFU/Seimei view of local U/LIRGs~

Author(s): Yoshiki Toba (NAOJ), Satoshi Yamada (RIKEN), Kazuya Matsubayashi (U. of Tokyo), Koki Terao (NAOJ), Aoi Moriya (Nara Women's U.), Yoshihiro Ueda (Kyoto U.), and GOLAS-KOOLS collaboration

Presenter: Yoshiki Toba (NAOJ)

We present ionized gas properties of 9 local ultra/luminous infrared galaxies (U/LIRGs) at z < 0.04 through IFU observations with KOOLS-IFU on Seimei Telescope. The observed targets are drawn from the Great Observatories All-sky LIRG Survey (GOALS), covering a wide range of merger stages. We successfully detect emission lines such as Hβ, [OIII]λ5007, Hα, [NII]λλ6549,6583, and [SII]λλ6717,6731 with a spectral resolution of R = 1500-2000, which provides (i) spatially-resolved (∼200-700 pc) moment map of ionized gas and (ii) diagnostics for active galactic nucleus (AGN) within the central ∼3-11 kpc in diameter for our sample. We find that [OIII] outflow that is expected to be driven by AGN tends to be more robust (i) towards the galactic center and (ii) as a sequence of the merger stage. In particular, the outflow strength in the late-stage (stage D) mergers is about 1.5 times stronger than that in the early-stage (stage B) mergers, which indicates that galaxy mergers could induce AGN-driven outflow and play an essential role in the co-evolution of galaxies and supermassive black holes (SMBHs) (Toba et al. 2022, PASJ, 74, 6).