The Column Density Distribution of the Lyman-Alpha Forest: A Measure of Small Scale Power
نویسندگان
چکیده
Lam Hui, Nickolay Y. Gnedin and Yu Zhang Absorption lines in the Lyα forest can be thought of as peaks in neutral hydrogen density along lines of sight. The column density distribution (the number density of absorption lines as a function of column density) is then a statistic of density peaks, which contains information about the underlying power spectrum. In particular, we show that the slope of the distribution provides a measure of power on scales smaller than those probed by studies of present-day large scale structure.
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