A.D.Smirnov (Yaroslavl University)

 

Color symmetry effects in quark-lepton physics.

 

A minimal extension of the Standard Model (SM) containing the four color quark--lepton symmetry with Higgs mechanism of fermion mass generation is investigated as a possible variant of new physics beyond SM. Mass limits for scalar leptoquark and scalar gluon doublets predicted in this approach are discussed with account of radiative correction $S, T, U$ parameters of Peskin--Takeuchi, new leptoquark mass limits are obtained from leptonic decays of neutral $K-$ and $B-$mesons, dominant decay modes of scalar leptoquark and scalar gluon doublets are found, scalar leptoquark contributions into specific rare $t-$quark decays are analysed, specific $Z'-$boson features are considered and some other effects of color quark--lepton symmetry at present and future collider energies are discussed.