2010/12/07 by Baojiu Li, Lindsay King, Lindsay J. King +4 · 23 citations
Physics and Astronomy · #Algorithm #Astrophysics #Computation #Computer science #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gamma-ray bursts and supernovae #Geometry #Gravitational lens #Grid #Line-of-sight #Optics #Physics #Ray tracing (physics) #Redshift #Stellar, planetary, and galactic studies #Weak gravitational lensing #astro-ph.CO
paper · pdf · doi:10.1111/j.1365-2966.2011.18754.x
published in Monthly Notices of the Royal Astronomical Society 415(1), 881-892 (Oxford University Press) · 13 pages, 5 figures
arxiv created 2010/12/07 · openalex publication_date 2011/05/25 · arxiv updated 2015/03/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We propose a new ray-tracing algorithm to measure the weak-lensing shear and convergence fields directly from N-body simulations. We calculate the deflection of the light rays lensed by the 3D mass density field or gravitational potential along the line of sight on a grid-by-grid basis, rather than using the projected 2D lens planes. Our algorithm uses simple analytic formulae instead of numerical integrations in the computation of the projected density field along the line of sight, and so is computationally efficient and straightforward to implement. This will prove valuable in the interpretation of data from the next generation of surveys that will image many thousands of square degrees of sky.