The rare t-quark decays t→clj+lk−, t→cνj~νk via the scalar leptoquark doublets are investigated in the minimal four
color symmetry model with the Higgs mechanism of the quark-lepton mass
splitting. The partial widths of these decays are calculated and the total
width of the charged lepton mode Γ(t→cl+′l−)=∑j,kΓ(t→clj+lk−) and the total width of the neutrino mode Γ(t→cν~′ν)=∑j,kΓ(t→cνj~νk) are found. The corresponding branching ratios are shown to be Br(t→cl+′l−)≈(3.5−0.4)10−5,Br(t→cν~′ν)≈(7.1−0.8)10−5 for the scalar leptoquark
masses mS=180−250GeV and for the appropriate values (sinβ≈0.2) of the mixing angle of the model. The search for such decays at
LHC may be of interest.Comment: 18 pages, 2 figures, 1 table, to be published in Modern Physics
Letters A; corrected typo