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arXiv · 1908.03854

Wide-angle redshift-space distortions at quasi-linear scales: cross-correlation functions from Zel'dovich approximation

Atsushi Taruya·Shohei Saga·Michel-Andrès Breton·Yann Rasera·Tomohiro Fujita
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Abstract

Redshift-space distortions (RSD) in galaxy redshift surveys generally break both the isotropy and homogeneity of galaxy distribution. While the former aspect is particularly highlighted as a probe of growth of structure induced by gravity, the latter aspect, often quoted as wide-angle RSD but ignored in most of the cases, will become important and critical to account for as increasing the statistical precision in next-generation surveys. However, the impact of wide-angle RSD has been mostly studied using linear perturbation theory. In this paper, employing the Zel'dovich approximation, i.e., first-order Lagrangian perturbation theory for gravitational evolution of matter fluctuations, we present a quasi-linear treatment of wide-angle RSD, and compute the cross-correlation function. The present formalism consistently reproduces linear theory results, and can be easily extended to incorporate relativistic corrections (e.g., gravitational redshift).

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Atsushi Taruya, Shohei Saga, Michel-Andrès Breton, Yann Rasera, Tomohiro Fujita. 2019-12-19. Wide-angle redshift-space distortions at quasi-linear scales: cross-correlation functions from Zel'dovich approximation. https://doi.org/10.1093/mnras%2Fstz3272

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