{"paper":{"title":"Effects of an extra $Z'$ gauge boson on the top quark decay $t --> c \\gamma$","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"A. Cordero-Cid, G. Tavares-Velasco, J. J. Toscano","submitted_at":"2005-07-11T23:49:53Z","abstract_excerpt":"The effects of an extra $Z'$ gauge boson with family nonuniversal fermion couplings on the rare top quark decay $t --> c $gamma$ are first examined in a model independent way and then in the minimal 331 model. It is found that the respective branching fraction is at most of the order of $10^{-8}$ for $m_{Z'}=500$ GeV and dramatically decreases for a heavier $Z'$ boson. This results is in sharp contrast with a previous evaluation of this decay in the context of topcolor assisted technicolor models, which found that $B(t --> c \\gamma)\\sim 10^{-6}$ for $m_{Z'}=1$ TeV."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0507135","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"}