2015MNRAS.454.1573K

We present mid-infrared (MIR) luminosity functions (LFs) of local (z < 0.3) star-forming (SF) galaxies in the AKARI's North Ecliptic Pole (NEP)-Wide survey field. In order to derive more accurate LF, we used spectroscopic sample only. Based on the NEP-Wide point source catalogue containing a large number of infrared (IR) sources distributed over the wide (5.4 deg2) field, we incorporated the spectroscopic redshift (z) data for ∼ 1790 selected targets obtained by optical follow-up surveys with MMT/Hectospec and WIYN/Hydra. The AKARI's continuous 2-24 µm wavelength coverage as well as photometric data from optical u* band to near-infrared H band with the spectroscopic redshifts for our sample galaxies enable us to derive accurate spectral energy distributions (SEDs) in the MIR. We carried out SED fit analysis and employed 1/Vmax method to derive the MIR (e.g. 8, 12, and 15 µm rest-frame) LFs. We fit our 8 µm LFs to the double power-law with the power index of α = 1.53 and β = 2.85 at the break luminosity 4.95x109L_☉. We made extensive comparisons with various MIR LFs from several literatures. Our results for local galaxies from the NEP region are generally consistent with other works for different fields over wide luminosity ranges. The comparisons with the results from the NEP-Deep data as well as other LFs imply the luminosity evolution from higher redshifts towards the present epoch.