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Mg II Detection in the Lyman Alpha Forest: Metal Rich Cloud or LSB/Dwarf Galaxy?

Christopher W. Churchill·Vincent Le Brun
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Abstract

We report the detection of Mg II absorption in two Lyman alpha forest clouds along the line of sight to PKS 0454+039. These clouds, at redshifts z=0.6248 and z=0.9315, respectively, also have strong Fe II absorption. We present results on the z=0.9315 cloud. The upper limit on log N(HI) is 16.5 cm^-2. Based upon UV background photoionization models, we infer that the cloud has super-solar metallicity. Photoionization by a late-type stellar population is ruled out.

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Christopher W. Churchill, Vincent Le Brun. 1997-09-12. Mg II Detection in the Lyman Alpha Forest: Metal Rich Cloud or LSB/Dwarf Galaxy?. https://arxiv.org/abs/astro-ph/9707155

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