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Testing flavor-changing neutral currents in the rare decays t->cViVj

J. L. Diaz-Cruz·M. A. Perez·G. Tavares-Velasco·J . J. Toscano
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Abstract

We discuss the Flavor-Changing Neutral Current (FCNC) decays of the top quark t -> c Vi Vj (Vi=gamma, Z, g) in the framework of the Standard Model (SM) and in a two-higgs doublet model (2HDM) with tree-level FCNC couplings. While in the SM the expected branching ratios are extremelly small, in the 2HDM they may be sizable, of order 10^(-5) - 10^(-5), and thus accesible at the CERN LHC. We conclude with the interesting observation that the FCNC decay modes may not be equally suppressed as their corresponding decays t ->c Vi in this 2HDM.

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J. L. Diaz-Cruz, M. A. Perez, G. Tavares-Velasco, J . J. Toscano. 1999-07-30. Testing flavor-changing neutral currents in the rare decays t->cViVj. https://doi.org/10.1103/physrevd.60.115014

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