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arXiv · 1005.4019

Minimally Parametric Constraints on the Primordial Power Spectrum from Lyman-alpha

Simeon Bird
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Abstract

Current analyses of the Lyman-alpha forest assume that the primordial power spectrum of density perturbations obeys a simple power law, a strong theoretical assumption which should be tested. Employing a large suite of numerical simulations which drop this assumption, we reconstruct the shape of the primordial power spectrum using Lyman-alpha data from the Sloan Digital Sky Survey (SDSS). Our method combines a minimally parametric framework with cross-validation, a technique used to avoid over-fitting the data. Future work will involve predictions for the upcoming Baryon Oscillation Sky Survey (BOSS), which will provide new Lyman-alpha data with vastly decreased statistical errors.

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Simeon Bird. 2010-05-21. Minimally Parametric Constraints on the Primordial Power Spectrum from Lyman-alpha. https://arxiv.org/abs/1005.4019

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