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arXiv · astro-ph/9807068

Recovery of the Shape of the Mass Power Spectrum from the Lyman-alpha Forest

Lam Hui
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Abstract

We propose a method for recovering the shape of the mass power spectrum on large scales from the transmission fluctuations of the Lyman-alpha forest, which takes into account directly redshift-space distortions. The procedure, in discretized form, involves the inversion of a triangular matrix which projects the mass power spectrum in 3-D real-space to the transmission power spectrum in 1-D redshift-space. We illustrate the method by performing a linear calculation relating the two. A method that does not take into account redshift-space anisotropy tends to underestimate the steepness of the mass power spectrum, in the case of linear distortions. The issue of the effective bias-factor for the linear distortion kernel is discussed.

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Lam Hui. 1998-07-09. Recovery of the Shape of the Mass Power Spectrum from the Lyman-alpha Forest. https://doi.org/10.1086/307134

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