THE CONTRIBUTION OF HI-RICH GALAXIES TO THE DAMPED Ly-α ABSORBER
نویسنده
چکیده
We present a study of the expected properties of the low redshift damped Ly-α absorber population determined from a sample of HI-selected galaxies in the local universe. We use measurements of the number density and HI cross-section of galaxies to show that the total HI cross-section at column densities sufficient to produce damped Ly-α absorption is consistent with no evolution of the absorber population. We also find that the dN/dz distribution is dominated by galaxies with HI masses near 10 M⊙. However, because of the large dispersion in the correlation between HI mass and stellar luminosity, we find that the distribution of dN/dz as a function of LJ is nearly flat. Additionally, we demonstrate that the linewidths of the HI-selected galaxies are roughly consistent with the kinematics of damped Ly-α absorbers.
منابع مشابه
The Contribution of HI - rich Galaxies to the Damped
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