  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 H$\beta$, [OIII]$\lambda$5007, H$\alpha$,
[NII]$\lambda\lambda$6549,6583, and [SII]$\lambda\lambda$6717,6731 with a
spectral resolution of $R$ = 1500-2000, which provides (i) spatially-resolved
($\sim$200-700 pc) moment map of ionized gas and (ii) diagnostics for active
galactic nucleus (AGN) within the central $\sim$3--11 kpc in diameter for our
sample. We find that [OIII] outflow that is expected to be driven by AGN tends
to be stronger (i) towards the galactic center and (ii) as a sequence of 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-state (stage B) mergers,
which indicates that galaxy mergers could induce AGN-driven outflow and play an
important role in the co-evolution of galaxies and supermassive black holes.
