2007/12/02 by Huanjun Zhang, Huan-Jun Zhang · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.77.057501
published as Phys.Rev.D77:057501,2008 · 11 pages, 4 figures
arxiv created 2007/12/02 · openalex publication_date 2008/03/03 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The topcolor-assisted technicolor (TC2) model predicts several pseudoscalars called top-pions and at loop level they can induce the flavor-changing neutral-current (FCNC) top-quark decay t\ensuremath→cgg which is extremely suppressed in the standard model (SM). We find that in the allowed parameter space the TC2 model can greatly enhance such a FCNC decay and push the branching ratio up to 10^\ensuremath-3, which is much larger than the predictions in the SM (10^\ensuremath-9) and in the minimal supersymmetric model (10^\ensuremath-4). We also compare the result with the two-body FCNC decay t\ensuremath→cg and find that the branching ratio of t\ensuremath→cgg is at the same order as t\ensuremath→cg. Such enhanced FCNC top-quark decays may serve as a good probe of the TC2 model at the future top-quark factory.