We present a gravitational lensing model of MACS J1149.5+2223 using ultra-deep Hubble Frontier Fields imaging data and spectroscopic redshifts from HST grism and VLT/MUSE spectroscopic data. We create total mass maps using 38 multiple images (13 sources) and 608 weak lensing galaxies, as well as 100 multiple images of 31 star-forming regions in the galaxy that hosts Supernova Refsdal. We find good agreement with a range of recent models within the HST field of view. We present a map of the ratio of projected stellar mass to total mass (f⋆), and find that the stellar mass fraction for this cluster peaks on the primary BCG. Averaging within a radius of 0.3 Mpc, we obtain a value of ⟨f⋆⟩=0.012−0.003+0.004, consistent with other recent results for this ratio in cluster environments, though with a large global error (up to δf⋆=0.005) primarily due to the choice of an IMF. We compare values of f⋆ and measures of star formation efficiency for this cluster to other Hubble Frontier Fields clusters studied in the literature, finding that MACS1149 has a higher stellar mass fraction than these other clusters, but a star formation efficiency typical of massive clusters.
@article{arxiv.1806.00698,
title = {Mass Modeling of Frontier Fields Cluster MACS J1149.5+2223 Using Strong and Weak Lensing},
author = {Emily Quinn Finney and Maruša Bradač and Kuang-Han Huang and Austin Hoag and Takahiro Morishita and Tim Schrabback and Tommaso Treu and Kasper Borello Schmidt and Brian C. Lemaux and Xin Wang and Charlotte Mason},
journal= {arXiv preprint arXiv:1806.00698},
year = {2018}
}
Comments
15 pages, 6 figures, published in ApJ May 23, 2018