Аннотация:We discuss the three-body decays ${t}_{1}\ensuremath{\rightarrow}{W}^{+}b{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{1}^{0},$ ${t}_{1}\ensuremath{\rightarrow}{H}^{+}b{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{1}^{0},$ ${t}_{1}\ensuremath{\rightarrow}b{l}_{i}^{+}{\ensuremath{\nu}}_{l},$ and ${t}_{1}\ensuremath{\rightarrow}b{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\nu}}}_{l}{l}^{+}(l=e,\ensuremath{\mu},\ensuremath{\tau})$ of the lighter top squark ${t}_{1}$ within the minimal supersymmetric standard model. We give the complete analytical formulas for the decay widths and present a numerical study in view of an upgraded Fermilab Tevatron, the CERN LHC, and a future lepton collider demonstrating the importance of these decay modes.
