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arXiv · 1612.00458

Gas Accretion via Lyman Limit Systems

Nicolas Lehner
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Abstract

In cosmological simulations, a large fraction of the partial Lyman limit systems (pLLSs; 16 2) redshifts. Here I discuss unambiguous evidence for metal-poor gas at all z probed by the pLLSs and LLSs. At z<1, all the pLLSs and LLSs so far studied are located in the CGM of galaxies with projected distances <100-200 kpc. Regardless of the exact origin of the low-metallicity pLLSs/LLSs, there is a significant mass of cool, dense, low-metallicity gas in the CGM that may be available as fuel for continuing star formation in galaxies over cosmic time. As such, the metal-poor pLLSs and LLSs are currently among the best observational evidence of cold, metal-poor gas accretion onto galaxies.

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Nicolas Lehner. 2016-12-01. Gas Accretion via Lyman Limit Systems. https://doi.org/10.1007/978-3-319-52512-9_6

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