The Column Density Distribution of the Lyman-Alpha Forest: A Measure of Small Scale Power

Lam Hui; Nickolay Y. Gnedin; Yu Zhang

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arXiv · astro-ph/9702167

The Column Density Distribution of the Lyman-Alpha Forest: A Measure of Small Scale Power

Lam Hui·Nickolay Y. Gnedin·Yu Zhang

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Abstract

Absorption lines in the Lyman-alpha 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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Lam Hui, Nickolay Y. Gnedin, Yu Zhang. 1997-02-19. The Column Density Distribution of the Lyman-Alpha Forest: A Measure of Small Scale Power. https://arxiv.org/abs/astro-ph/9702167

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