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arXiv · 1411.1249

Nonlinear Behavior of Baryon Acoustic Oscillations in Redshift Space from the Zel'dovich Approximation

Nuala McCullagh·Alexander S. Szalay
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Abstract

Baryon acoustic oscillations (BAO) are a powerful probe of the expansion history of the universe, which can tell us about the nature of dark energy. In order to accurately characterize the dark energy equation of state using BAO, we must understand the effects of both nonlinearities and redshift space distortions on the location and shape of the acoustic peak. In a previous paper we introduced a novel approach to 2nd order perturbation theory in configuration space using the Zel'dovich approximation, and presented a simple result for the first nonlinear term of the correlation function. In this paper, we extend this approach to redshift space. We show how perform the computation, and present the analytic result for the first nonlinear term in the correlation function. Finally, we validate our result through comparison to numerical simulations.

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Nuala McCullagh, Alexander S. Szalay. 2014-11-05. Nonlinear Behavior of Baryon Acoustic Oscillations in Redshift Space from the Zel'dovich Approximation. https://doi.org/10.1088/0004-637x%2F798%2F2%2F137

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