{"paper":{"title":"Growing a `Cosmic Beast': Observations and Simulations of MACS J0717.5+3745","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"A. Robertson (ICC, C. Baugh (ICC, C. Dalla Vecchia (Inst. Astrof. de Canarias, D. Barnes (Manchester, D. Eckert (MPE), D. Harvey (EPFL), Durham), E. Jullo (LAM), E. Medezinski (Princeton), Hawaii), H. Ebeling (IfA, J.-P. Kneib (EPFL, J. Schwinn (Heidelberg), K. Umetsu (ASIAA), LAM), MIT), M. Jauzac (CEA, M. Limousin (LAM), M. Nonino (INAF), M. Schaller (ICC, P. Natarajan (Yale), R. Massey (CEA, S. I. Tam (CEA, S. T. Kay (Manchester), U. de La Laguna), Y. Bah\\'e (Leiden)","submitted_at":"2017-11-03T20:32:36Z","abstract_excerpt":"We present a gravitational lensing and X-ray analysis of a massive galaxy cluster and its surroundings. The core of MACS\\,J0717.5+3745 ($M(R<1\\,{\\rm Mpc})\\sim$\\,$2$$\\times$$10^{15}\\,\\msun$, $z$=$0.54$) is already known to contain four merging components. We show that this is surrounded by at least seven additional substructures with masses ranging from $3.8-6.5\\times10^{13}\\,\\msun$, at projected radii $1.6$ to $4.9$\\,Mpc. We compare MACS\\,J0717 to mock lensing and X-ray observations of similarly rich clusters in cosmological simulations. The low gas fraction of substructures predicted by simul"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1711.01324","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}