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arXiv · astro-ph/0505284

The cosmic shear three-point functions

K. Benabed·R. Scoccimarro
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Abstract

We investigate the three-point functions of the weak lensing cosmic shear, using both analytic methods and numerical results from N-body simulations. The analytic model, an isolated dark matter halo with a powerlaw profile chosen to fit the effective index at the scale probed, can be used to understand the basic properties of the eight three-point functions observed in simulations. We use this model to construct a single three-point function estimator that "optimally" combines the eight three-point functions. This new estimator is an alternative to Map statistics and provides up to a factor of two improvement in signal to noise compared to previously used combinations of cosmic shear three-point functions.

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K. Benabed, R. Scoccimarro. 2005-05-13. The cosmic shear three-point functions. https://doi.org/10.1051/0004-6361%3A20054125

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