The 2 to 24 micron source counts from the AKARI North Ecliptic Pole
  survey
  We present herein galaxy number counts of the nine bands in the 2-24 micron
range on the basis of the AKARI North Ecliptic Pole (NEP) surveys. The number
counts are derived from NEP-deep and NEP-wide surveys, which cover areas of 0.5
and 5.8 deg2, respectively. To produce reliable number counts, the sources were
extracted from recently updated images. Completeness and difference between
observed and intrinsic magnitudes were corrected by Monte Carlo simulation.
Stellar counts were subtracted by using the stellar fraction estimated from
optical data. The resultant source counts are given down to the 80%
completeness limit; 0.18, 0.16, 0.10, 0.05, 0.06, 0.10, 0.15, 0.16, and 0.44
mJy in the 2.4, 3.2, 4.1, 7, 9, 11, 15, 18 and 24 um bands, respectively. On
the bright side of all bands, the count distribution is flat, consistent with
the Euclidean Universe, while on the faint side, the counts deviate, suggesting
that the galaxy population of the distant universe is evolving. These results
are generally consistent with previous galaxy counts in similar wavebands. We
also compare our counts with evolutionary models and find them in good
agreements. By integrating the models down to the 80% completeness limits, we
calculate that the AKARI NEP-survey revolves 20%-50% of the cosmic infrared
background, depending on the wavebands.
