Abstract
The properties of warm IRAS Seyfert galaxies, those with abnormally blue 25 micron to 60 micron flux ratios, are discussed. It is shown that more than 70 percent of galaxies with F(60)/F(25) of 3 or less for which optical spectroscopy is available are Seyfert galaxies and that most are of type 2. The newly discovered type 2 Seyferts have a space density comparable to known Markarian Seyfert galaxies but less than type 2 Seyferts in the CfA redshift survey. The 25 micron emission from most Seyferts appears to be dominated by their nuclei; the evidence indicates that Seyferts with steeply rising far-infrared spectra (cold Seyferts) are dominated by star-formation regions at 60 and 100 microns. Cold Seyferts are found to have significantly lower 25 micron luminosities. The nuclear optical emission-line ratios of cold type 2 Seyferts are intermediate between those of warm Seyferts and H II regions, suggesting that regions of massive star formation exist in the immediate vicinity of the nuclei. 26 references.
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