Lenticular galaxy IC 719: current building of the counterrotating
  large-scale stellar disk
  We have obtained and analyzed long-slit spectral data for the lenticular
galaxy IC 719. In this gas-rich S0 galaxy, its large-scale gaseous disk
counterrotates the global stellar disk. Moreover in the IC 719 disk we have
detected a secondary stellar component corotating the ionized gas. By using
emission-line intensity ratios, we have proved the gas excitation by young
stars and so are claiming current star formation, most intense in a ring-like
zone at the radius of 10" (1.4 kpc). The oxygen abundance of the gas in the
starforming ring is about half of the solar abundance. Since the stellar disk
remains dynamically cool, we conclude that smooth prolonged accretion of the
external gas from a neighboring galaxy provides urrent building of the thin
large-scale stellar disk.
