Rare B decays in the {F} - {{SU}}( {5} ) model

In the testable Flipped SU(5) x U( 1)x model with TeV-scale vector-like particles from F-theory model building clubbed as the F-SU(5) model, we study the vector-like quark contributions to B physics processes, including the quark mass spectra, Feynman rules, new operators and Wilson coefficients, etc. We focus on the implications of the vector-like quark mass scale on B physics. We find that there exists the (s) over bar bZ interaction at tree level, and the Yukawa interactions are changed. Interestingly, different from many previous models, the effects of vector-like quarks on rare B decays such as B -> X-s gamma and B -> X(s)l(+)l(-) do not decouple in some viable parameter space, especially when the vectorlike quark masses are comparable to the charged Higgs boson mass. Under the constraints from B -> X-s gamma and B -> X(s)l(+)l(-) the latest measurement for B-s -> mu(+)mu(-) can be explained naturally, and the branching ratio of B-s -> l(+)l(-)gamma can be up to (4 similar to 5) x 10(-8). The non-decoupling, effects are much more predictable and thus the F-SU(5) model may be tested in the near future experiments.