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Arxiv: JWST Photometry of Globular Clusters in Abell 2744. II: luminosity and color distributions Published: 4/16/2024 9:00:00 PM Updated: 4/16/2024 9:00:00 PM

Paper abstract: Deep JWST imaging of the giant galaxy cluster Abell 2744, at redshiftz=0.308, is used to explore the features of its rich population of globularclusters (GCs), building on our initial survey of the system (Harris &Reina-Campos 2023). We use the photometry of more than 10,000 GCs over athree-magnitude range to construct the GC luminosity function (GCLF) and colordistribution (CDF). These results now specifically account for photometricincompleteness as a function of location relative to the five giant galaxiesthat dominate the gravitational potential of A2744. The total GC population inA2744 is estimated at N_{\rm GC} >= 1.1 \times 10^5, consistent with itshigh total mass. We also directly compare the observed distributions withtheoretical predictions for GC populations drawn from the recent EMP-Pathfindersimulations (Reina-Campos et al. 2022), viewed at the same 3.5 Gyr lookbacktime as the cluster. The simulations match the observations well, with the onlynotable disagreement being that the simulations predict larger numbers of GCsat high metallicity formed after z~eq2 than are seen in the data.