Cosmological Adventures in the Lyman Forest
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منابع مشابه
Probing the universe with the Lyman-alpha forest: III. The mean opacity of the IGM
I apply the well controlled Hydro-PM approximation of Gnedin & Hui to study the consistency between the column density distribution of the Lyman-alpha forest and the mean opacity of the IGM for 25 different flat cosmological scenarios, including variants of the standard CDM, tilted CDM, CDM with a cosmological constant, and CHDMmodels. I show that observational data of Press, Rybicki, and Schne...
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In recent years, a remarkably simple physical picture of the Lyman-alpha forest has emerged, which allows detailed predictions to be made and turns the forest into a powerful probe of cosmology. We point out ways in which such a picture can be tested observationally, and explore three areas in which the Lyman-alpha forest can yield valuable constraints: the reionization history, the primordial ...
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We develop an analytical method based on the lognormal approximation to compute the column density distribution of the Lyman-alpha forest in the low column density limit. We compute the column density distributions for six different cosmological models and found that the standard, COBE -normalized CDM model cannot fit the observations of the Lyman-alpha forest at z = 3. The amplitude of the flu...
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We investigate possible systematic errors in the recent measurement of the matter power spectrum from the Lyman-alpha forest by Croft et al. (2001). We find that for a large set of prior cosmological models the Croft et al. result holds quite well, with systematic errors being comparable to random ones, when a dependence of the recovered matter power spectrum on the cosmological parameters at z...
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