The Frontier Fields Lens Modelling Comparison Project
Presented by Massimo Meneghetti
Jet Propulsion Laboratory, California Institute of Technology
Thursday, February 5, 2015
4:00 P.M. in 169-336
The Hubble Frontier Fields Initiative is the current major effort of the Hubble Space Telescope, which is undertaking a revolutionary deep field observing program to peer deeper into the Universe than ever done before. The program is targeting 6 galaxy clusters, selected for being among the strongest gravitational lenses in the universe. The principal goal is to use the clusters magnification power to allow the detection and the characterization of galaxies at high redshift (z~-8-11). This is of fundamental importance for a comprehensive understanding of star and galaxy formation and how this is related to cosmic reionization. Understanding the intrinsic properties of distant lensed galaxies requires accurate determination of the lens magnification. Magnification estimates are provided by lens models which are built upon sets of multiple images of galaxies in the cluster background as well as the spatial distribution of the cluster galaxies. Several groups are currently involved in the lens modelling of the Frontier Fields, using different algorithms to perform the reconstructions. In collaboration with all these groups, we are using mock HST observations mimicking the depth and the quality of the Frontier Fields data to test the performance of all these algorithms against know lens mass distributions. This is allowing us to identify the systematics of the methods and propose improvements, with the aim of converging to the most robust and accurate cluster mass reconstructions. In this talk I will report on the results of the analysis of the first two round of simulations and illustrate the plans for the future.