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arXiv · astro-ph/9812300

The Ray Bundle method for calculating weak magnification by gravitational lenses

C. J. Fluke·R. L. Webster·Daniel J. Mortlock
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Abstract

We present here an alternative method for calculating magnifications in gravitational lensing calculations -- the Ray Bundle method. We provide a detailed comparison between the distribution of magnifications obtained compared with analytic results and conventional ray-shooting methods. The Ray Bundle method provides high accuracy in the weak lensing limit, and is computationally much faster than (non-hierarchical) ray shooting methods to a comparable accuracy. The Ray Bundle method is a powerful and efficient technique with which to study gravitational lensing within realistic cosmological models, particularly in the weak lensing limit.

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C. J. Fluke, R. L. Webster, Daniel J. Mortlock. 1998-12-16. The Ray Bundle method for calculating weak magnification by gravitational lenses. https://doi.org/10.1046/j.1365-8711.1999.02534.x

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