CONSEQUENCES OF H-II REGION MODELS FOR ABSORPTION SYSTEMS IN THE QUASAR SPECTRA

We have studied various consequences of the hypothesis that H II regio ns around massive stars give rise to metal-line absorption systems see n in the quasar spectra. Based on the necessary star formation rate in the absorbing galaxy and its expected surface brightness in Ly alpha, as well as on the ratio of the expected number of low-ionization to h igh-ionization absorption systems, we conclude that H II regions can a t most account for 10% of the observed absorption systems in quasar sp ectra.