Far‐Infrared Photometry of a Statistical Sample of Late‐Type Virgo Cluster Galaxies

We present deep diffraction-limited far-infrared ( FIR) strip maps of a sample of 63 galaxies later than S0 and brighter than B-T = 16.8, selected from the Virgo Cluster Catalogue of Binggeli, Sandage, & Tammann. The ISOPHOT instrument on board the Infrared Space Observatory was used to achieve sensitivities typically an order of magnitude deeper than IRAS in the 60 and 100 mum bands and to reach the confusion limit at 170 mum. The averaged 3 sigma upper limits for integrated flux densities of point sources at 60, 100, and 170 mum are 43, 33, and 58 mJy, respectively. A total of 63.5% are detected at all three wavelengths. The highest detection rate (85.7%) is in the 170 mum band. In many cases the galaxies are resolved, allowing the scale length of the infrared disks to be derived from the oversampled brightness profiles in addition to the spatially integrated emission. The data presented should provide the basis for a variety of statistical investigations of the FIR spectral energy distributions of gas-rich galaxies in the local universe spanning a broad range in star formation activity and morphological types, including dwarf systems and galaxies with rather quiescent star formation activity.