Hubble Frontier Fields : A High Precision Strong Lensing Analysis of Galaxy Cluster MACSJ0416.1-2403 using ~200 Multiple Images

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We present a high-precision mass model of the galaxy cluster MACSJ0416.1-2403, based on a strong-gravitational-lensing analysis of the recently acquired Hubble Space Telescope Frontier Fields (HFF) imaging data.

• Taking advantage of the unprecedented depth provided by HST/ACS observations in three passbands, we identify 51 new multiply imaged galaxies, quadrupling the previous census and bringing the grand total to 68, comprising 194 individual lensed images.
• Having selected a subset of the 57 most securely identified multiply imaged galaxies, we use the Lenstool software package to constrain a lens model comprised of two cluster-scale dark-matter halos and 98 galaxy-scale halos.
• Our best-fit model predicts image positions with an $RMS$ error of 0.68'', which constitutes an improvement of almost a factor of two over previous, pre-HFF models of this cluster.