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arXiv · 1604.08914

Lensing corrections to the $E_g(z)$ statistics from large scale structure

Azadeh Moradinezhad Dizgah·Ruth Durrer
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Abstract

We study the impact of the often neglected lensing contribution to galaxy number counts on the $E_g$ statistics which is used to constrain deviations from GR. This contribution affects both the galaxy-galaxy and the convergence-galaxy spectra, while it is larger for the latter. At higher redshifts probed by upcoming surveys, neglecting this term induces a substantial error in the spectra and therefore on the $E_g$ statistics which is constructed from the combination of the two. Moreover, including it, renders the $E_g$ statistics scale and bias-dependent and hence puts into question its very objective.

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Azadeh Moradinezhad Dizgah, Ruth Durrer. 2016-10-07. Lensing corrections to the $E_g(z)$ statistics from large scale structure. https://doi.org/10.1088/1475-7516%2F2016%2F09%2F035

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