Evolution of Infrared Luminosity functions of Galaxies in the AKARI
  NEP-Deep field: Revealing the cosmic star formation history hidden by dust
  Dust-obscured star-formation becomes much more important with increasing
intensity, and increasing redshift. We aim to reveal cosmic star-formation
history obscured by dust using deep infrared observation with the AKARI.
  We construct restframe 8um, 12um, and total infrared (TIR) luminosity
functions (LFs) at 0.15<z<2.2 using 4128 infrared sources in the AKARI NEP-Deep
field. A continuous filter coverage in the mid-IR wavelength (2.4, 3.2, 4.1, 7,
9, 11, 15, 18, and 24um) by the AKARI satellite allows us to estimate restframe
8um and 12um luminosities without using a large extrapolation based on a SED
fit, which was the largest uncertainty in previous work. We have found that all
8um (0.38<z<2.2), 12um (0.15<z<1.16), and TIR LFs (0.2<z<1.6), show a
continuous and strong evolution toward higher redshift. In terms of cosmic
infrared luminosity density (Omega_IR), which was obtained by integrating
analytic fits to the LFs, we found a good agreement with previous work at
z<1.2, and that the Omega_IR evolves as propto (1+z)^4.4+-1.0. When we separate
contributions to Omega_IR by LIRGs and ULIRGs, we found more IR luminous
sources are increasingly more important at higher redshift. We found that the
ULIRG (LIRG) contribution increases by a factor of 10 (1.8) from z=0.35 to
z=1.4.
