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arXiv · 1708.01441

Weak lensing deflection of three-point correlation functions

Susan Pyne·Benjamin Joachimi·Hiranya V. Peiris
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Abstract

Weak gravitational lensing alters the apparent separations between observed sources, potentially affecting clustering statistics. We derive a general expression for the lensing deflection which is valid for any three-point statistic, and investigate its effect on the three-point clustering correlation function. We find that deflection of the clustering correlation function is greatest at around $z=2$. It is most prominent in regions where the correlation function varies rapidly, in particular at the baryon acoustic oscillation scale where it smooths out the peaks and troughs, reducing the peak-to-trough difference by about 0.1 percent at $z=1$ and around 2.3 percent at $z=10$. The modification due to lensing deflection is typically at the per cent level of the expected errors in a Euclid-like survey and therefore undetectable.

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Susan Pyne, Benjamin Joachimi, Hiranya V. Peiris. 2017-08-04. Weak lensing deflection of three-point correlation functions. https://doi.org/10.1088/1475-7516%2F2017%2F12%2F043

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