Physical constraints derived from FCNC in the 3-3-1-1 model

Abstract

Abstract We investigate several phenomena related to FCNCs in the $$\text {3-3-1-1}$$ 3-3-1-1 model. The sources of FCNCs at the tree-level from both the gauge and Higgs sectors are clarified. Experiments on the oscillation of mesons most stringently constrain the tree-level FCNCs. The lower bound on the new physics scale is imposed more tightly than in the previous, $$\text {M}_{\text {new}}>12 $$ M new > 12 TeV. Under this bound, the tree-level FCNCs make a negligible contribution to the $$\text {Br}(B_s \rightarrow \mu ^+ \mu ^-)$$ Br ( B s → μ + μ - ) , $$\text {Br}(B \rightarrow K^{*} \mu ^+ \mu ^-)$$ Br ( B → K ∗ μ + μ - ) and $$\text {Br}(B^{+}\rightarrow K^{+}\mu ^{+}\mu ^{-})$$ Br ( B + → K + μ + μ - ) . The branching ratio of radiative decay $$b \rightarrow s \gamma $$ b → s γ is enhanced by the ratio $$\frac{v}{u}$$ v u via diagrams with the charged Higgs mediation. In contrast, the charged currents of new gauge bosons significantly contribute to the decay process $$\mu \rightarrow e \gamma $$ μ → e γ .