Abstract We investigate several phenomena related to FCNCs in the $$\text {3-3-1-1}$$ 3-3-1-1 model. The sources of at tree-level from both gauge and Higgs sectors are clarified. Experiments on oscillation mesons most stringently constrain FCNCs. lower bound new physics scale is imposed more tightly tha...

We study the FCNC problems in 3-4-1-1 model a way different from previous work. The sources of at tree-level come both gauge and scalar sectors. show that most stringently bound on interactions comes meson oscillations. lower new physics scale is imposed more tightly than work, \(M_{new} > 22\) TeV. On allowed value domain physical scale, we contribution to BrB\(_s \rightarrow \mu^+ \mu^-)\)...