2009/06/30 by Adi Zitrin, Tom Broadhurst · 2 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Space Technology and Applications #astro-ph.CO
paper · pdf · doi:10.1088/0004-637x/703/2/l132
published as Astrophys.J.703:L132-L136,2009 · 5 pages, 5 figures, accepted to ApJ letters - minor changes made. High resolution figures available at ftp://wise-ftp.tau.ac.il/pub/adiz/macs1149.5+2223
arxiv created 2009/08/26 · openalex publication_date 2009/09/14 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We identify the largest known lensed images of a single spiral galaxy, lying close to the center of the distant cluster MACS J1149.5+2223 ( z = 0.544). These images cover a total area of and are magnified ≃200 times. Unusually, there is very little image distortion, implying that the central mass distribution is almost uniform over a wide area ( r ≃ 200 kpc) with a surface density equal to the critical density for lensing, corresponding to maximal lens magnification. Many fainter multiply lensed galaxies are also uncovered by our model, outlining a very large tangential critical curve, of radius r ≃ 170 kpc, posing a potential challenge for the standard LCDM cosmology. Because of the uniform central mass distribution, a particularly clean measurement of the mass of the brightest cluster galaxy is possible here, for which we infer stars contribute most of the mass within a limiting radius of ≃30 kpc, with a mass-to-light ratio of M / L B ≃ 4.5( M / L ) ☉ . This cluster with its uniform and central mass distribution acts analogously to a regular magnifying glass, converging light without distorting the images, resulting in the most powerful lens yet discovered for accessing the faint high- z universe.