| Abstract | A sensitive neutral hydrogen study was carried out on a sample of 145 galaxies with known redshift and with Hubble classification S0, S0/a, or Sa. New H I data were collected with the 305 m Arecibo telescope. The study covers galaxies both in and outside of the Virgo cluster, includes some faint galaxies (to mz = 14.0), and used only one central Arecibo beam per galaxy. In total, 64 galaxies are detected, including 25 pure S0 galaxies. However, in spite of the good sensitivity, many of the S0 galaxies are still undetected (while others give a very strong signal), indicating a very large range in the ratio of hydrogen mass to luminosity. The authors confirm that the detection probability for S0 galaxies is smaller inside the Virgo cluster than outside. Most Sa galaxies were detected, except in the Virgo cluster core, and the H I content of detected Sa galaxies is smaller inside the cluster than outside. The correlation of gas content with optical features and radio continuum properties is also discussed. |
