{"paper":{"title":"The Brightest Cluster X-ray Sources","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Andrew King","submitted_at":"2011-04-05T07:35:58Z","abstract_excerpt":"There have been several recent claims of black hole binaries in globular clusters. I show that these candidate systems could instead be ultracompact X-ray binaries (UCXBs) in which a neutron star accretes from a white dwarf. They would represent a slightly earlier evolutionary stage of known globular cluster UCXBs such as 4U 1820--30, with white dwarf masses $\\sim 0.2\\msun$, and orbital periods below 5 minutes. Accretion is slightly super--Eddington, and makes these systems ultraluminous sources (ULXs) with rather mild beaming factors $b \\sim 0.3$. Their theoretical luminosity function flatten"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1104.0751","kind":"arxiv","version":1},"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"}