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Precision {\tt MARS} Mass Reconstruction of Abell 2744: Synergizing the Largest Strong Lensing and Densest Weak Lensing Datasets from JWST Published: 8/28/2023 9:01:10 PM Updated: 8/28/2023 9:01:10 PM

Paper abstract: We present a new high-resolution free-form mass model of Abell 2744,combining both weak-lensing (WL) and strong-lensing (SL) datasets from JWST.The SL dataset comprises 286 multiple images, presenting the most extensive SLconstraint to date for a single cluster. The WL dataset, employing photo-zselection, yields a source density of ~ 350 arcmin^{-2}, marking the densestWL constraint ever. The combined mass reconstruction enables thehighest-resolution mass map of Abell 2744 within the ~ 1.8 Mpc\times1.8 Mpcreconstruction region to date, revealing the isosceles triangular structurewith two legs of ~ 1 Mpc and a base of ~ 0.6 Mpc. Although our algorithmMAximum-entropy ReconStruction ({\tt MARS}) is entirely blind to the clustergalaxy distribution, the resulting mass reconstruction remarkably well tracesthe brightest cluster galaxies with the five strongest mass peaks coincidingwith the five most luminous cluster galaxies. We do not detect any unusual masspeaks that are not traced by the cluster galaxies, unlike the findings inprevious studies. Our mass model shows the smallest scatters of SL multipleimages in both source (~0".05) and image (~0".1) planes, which are lower thanthe previous studies by a factor of ~ 4. Although {\tt MARS} represents themass field with an extremely large number of ~ 300,000 free parameters, itconverges to a solution within a few hours thanks to our utilization of thedeep learning technique. We make our mass and magnification maps publiclyavailable.