We report the results of an HI blind survey of 80 deg of the Virgo cluster, based on the 08° 16° strip of ALFALFA, the Arecibo Legacy Fast ALFA Survey. 187 HI sources of high significance are found providing a complete census of HI sources in this region of the Virgo cluster ( km s) with . 156/187 (83%) sources are identified with optical galaxies from the Virgo Cluster Catalogue (Binggeli et al. 1985, AJ, 90, 1681), all but 8 with late-type galaxies. Ten sources are not associated with optical galaxies and were found to correspond to tidally-disrupted systems (see Kent et al. 2007, ApJ, 665, L15; and Haynes et al. 2007, ApJ, 665, L19). The remaining 21 (11%) are associated with galaxies that are not listed in the Virgo Cluster Catalogue. For all sources with an optical counterpart in the Sloan Digital Sky Survey, we analyzed -band SDSS plates to measure optical structural parameters. We find that in the Virgo cluster: i) HI inhabits galaxies that are structurally similar to ordinary late-type galaxies; ii) their HI content can be predicted from their optical luminosity; iii) low surface brightness galaxies have low optical luminosity and contain small quantities of neutral hydrogen; iv) low surface brightness, massive Malin1 type galaxies are comfortably rare objects (less than 0.5%); v) there are no "dark-galaxies" with HI masses ; vi) less than 1% of early-type galaxies contain neutral hydrogen with (di Serego Alighieri et al. 2007, A&A, 474, 851).
- Galaxies: ISM
- Galaxies: clusters: individual: Virgo
- Galaxies: evolution
- galaxies: fundamental parameters