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An 18-cm OH and 21-cm H I survey of luminous far-infrared galaxies. II - H I properties
As a part of the present 18-cm OH and 21-cm H I survey of luminousfar-infrared galaxies, the paper provides H I data obtained at Nancayfor 88 IRAS galaxies, with FIR luminosity above 10 to the 10th solarluminosity. Among them, 64 are measured here for the first time. Whenrestricting to radial velocities smaller than 11,000 km/s, the detectionrate is equal to 85 percent, independent of the distance. These galaxiesappear as giant ones in dimension, total mass and total blue luminosity.All these parameters increase with increasing FIR luminosity. ExtremeFIR luminosity is thus related to gigantism, which could be the resultof mergers. These galaxies are also deficient in their relative H Icontent, in the sense that their global relative H I content issignificantly smaller than in classical galaxies of the Hubble sequence.
| The 12 micron galaxy sample. I - Luminosity functions and a new complete active galaxy sample
An all-sky 12 micron flux-limited sample of active galaxies was selectedfrom the IRAS Point Source Catalog. Most of the sample galaxies are inexisting catalogs, and 99 percent have measured redshifts. The 12-micronand the far-infrared luminosity functions of active and normal galaxiesare derived using IRAS co-added data. A total of 22 percent of thesample galaxies harbor active nuclei. The sample consists almost equallyof Seyfert 1, Seyfert 2, and LINER nuclei. The derived luminosityfuctions for Seyfert 1 and Seyfert 2 galaxies are indistinguishable fromthose of the optically selected CfA sample. Thus, 12 micron selection isthe most efficient available technique for finding complete activegalaxy samples.
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