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arXiv · 1105.1514

An analytic approach to baryon acoustic oscillations

Francesco Montanari·Ruth Durrer
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Abstract

The fitting formula for the location of the first acoustic peak in the matter power spectrum is revised. We discuss the physics that leads to baryon acoustic oscillations: the recombination history, the tight coupling approximation and the velocity overshoot effect. A new fitting formula is proposed, which is in accordance within 5% with numerical results for a suitable range of cosmological parameters, whereas previous results yield deviations of up to 20%. The crucial improvement turns out to be the accuracy of the recombination history.

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Francesco Montanari, Ruth Durrer. 2011-07-07. An analytic approach to baryon acoustic oscillations. https://doi.org/10.1103/physrevd.84.023522

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