The Properties of Infrared Galaxies in the Local Universe

The 60 μm selected IRAS Bright Galaxy Sample is used as a starting point to derive additional complete flux-limited samples of extragalactic objects at 12, 25, and 100 microns. With these complete samples the luminosity functions at all IRAS wavelengths are derived for the local Universe. These luminosity functions are used to determine the infrared emission of the local Universe. The maximum in the energy output of galaxies occurs at 100 microns. The infrared emission of galaxies at 12 and 25 micron represents 30% of the total infrared luminosity in the local Universe. The mean infrared colors of infrared selected galaxies vary systematically with infrared luminosity; the ratio S_v_(60 micron)/S_v_(100 micron) increases and S_v_(12 micron)/S_v_(25 micron) decreases with increasing infrared luminosity.