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arXiv · 1101.0054

A redshift distortion free correlation function at third order in the nonlinear regime

Kelai Meng·Jun Pan·Istvan Szapudi·Longlong Feng
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Abstract

The zeroth-order component of the cosine expansion of the projected three-point correlation function is proposed for clustering analysis of cosmic large scale structure. These functions are third order statistics but can be measured similarly to the projected two-point correlations. Numerical experiments with N-body simulations indicate that the advocated statistics are redshift distortion free within 10% in the non-linear regime on scales ~0.2-10Mpc/h. Halo model prediction of the zeroth-order component of the projected three-point correlation function agrees with simulations within ~10%. This lays the ground work for using these functions to perform joint analyses with the projected two-point correlation functions, exploring galaxy clustering properties in the framework of the halo model and relevant extensions.

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Kelai Meng, Jun Pan, Istvan Szapudi, Longlong Feng. 2010-12-30. A redshift distortion free correlation function at third order in the nonlinear regime. https://doi.org/10.1111/j.1365-2966.2011.18247.x

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