NEP deep survey at 11um

The data set covers 6 wavelength bands from 2.5 to 11um, with exposure times of 10-20 minutes. This field lies within the CFHT survey with four filter bands (g', r', i', z'), enabling us to establish nearly continuous spectral energy distributions (SEDs) for wavelengths ranging from 0.4 to 11um.

The main sample studied here consists of 72 sources whose 11um AB magnitudes are equal to or brighter than 18.5 (144uJy), which is complete to more than 90%. The 11um band has an advantage of sampling star-forming galaxies with low-to-medium redshifts, since the prominent PAH feature shifts into this band. As expected, we find that the majority (71%) of 11um bright sources are star-forming galaxies at 0.2~<z~<0.7 with L_IR_~10^10^-10^12^~L_{sun}_ based on detailed modelling of the SEDs.