English

A Lens Mapping Algorithm for Weak Lensing

Astrophysics 2009-10-31 v2

Abstract

We develop an algorithm for the reconstruction of the two-dimensional mass distribution of a gravitational lens from the observable distortion of background galaxies. From the measured reduced shear, the lens mapping is obtained, from which a mass distribution is derived. This is unlike other methods where the convergence ("kappa") is directly obtained. We show that this method works best for sub-critical lenses, but can be applied to a critical lens away from the critical lines. For finite fields the usual mass-sheet degeneracy is shown to exist in this method as well. We show that the algorithm reproduces the mass distribution within acceptable limits when applied to simulated noisy data.

Keywords

Cite

@article{arxiv.astro-ph/0002416,
  title  = {A Lens Mapping Algorithm for Weak Lensing},
  author = {Tarun Deep Saini and Somak Raychaudhury},
  journal= {arXiv preprint arXiv:astro-ph/0002416},
  year   = {2009}
}

Comments

4 pages, 6 figures, uses emulateapj5.sty (included); substantially revised; a slightly shorter version (fewer figures) will appear in Ap.J.Letters