THE LOCAL H i MASS FUNCTION
نویسنده
چکیده
The local H i mass function (HiMF), like the optical luminosity function, is an important observational input into models of cosmology and galaxy evolution. It is a helpful framework for assessing the number density of gas rich dwarf galaxies, which are easily missed in optically selected galaxy samples, as well as for determining the cosmological density of neutral gas at the present epoch. For H i masses larger than 108 M⊙ the HiMF is determined with reasonable accuracy and the same function is obtained from both optical and H i selected samples of galaxies. However, the faint tail below MHI < 10 7 M⊙ is still ill-constrained and leaves room for a population of gas rich dwarfs or free floating H i clouds which hypothetically could contribute significantly to the local gas density. Determining the faint tail far below H i masses of 107 M⊙ will be a great challenge for the future.
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تاریخ انتشار 1998