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arXiv · 0909.0822

A new stochastic approach to cumulative weak lensing

Kimmo Kainulainen·Valerio Marra
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Abstract

We study the weak gravitational lensing effects caused by a stochastic distribution of dark matter halos. We develop a simple approach to calculate the magnification probability distribution function which allows us to easily compute the magnitude bias and dispersion for an arbitrary data sample and a given universe model. As an application we consider the effects of single-mass large-scale cosmic inhomogeneities to the SNe magnitude-redshift relation, and conclude that such structures could bias the PDF enough to affect the extraction of cosmological parameters from the limited size of present-day SNe data samples. We also release turboGL, a simple and very fast (<= 1s) Mathematica code based on the method here presented.

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Kimmo Kainulainen, Valerio Marra. 2009-12-09. A new stochastic approach to cumulative weak lensing. https://doi.org/10.1103/physrevd.80.123020

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