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Correlation of Low z Lyman-alpha Absorbers with HI-selected Galaxies

Emma V. Ryan-Weber
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Abstract

In this work, observational evidence for the connection between low column density Lyman-alpha absorbers and large-scale structure traced by gas-rich galaxies is investigated. The HI Parkes All Sky Survey (HIPASS) galaxy catalogue is cross-correlated with known low redshift, low column density Lyman-alpha absorbers from the literature. The absorber-galaxy cross-correlation function shows that on scales from 1 to 10 h^-1 Mpc, absorbers are imbedded in halos with masses similar to that of galaxy groups. This statistical evidence suggests that galaxy groups could be the dominant environment of low column density Lyman-alpha absorbers at z=0.

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Emma V. Ryan-Weber. 2005-04-22. Correlation of Low z Lyman-alpha Absorbers with HI-selected Galaxies. https://doi.org/10.1017/s1743921305003121

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