Abstract:

In the report we consider rare B-meson decays with flavor changing neutral current transitions in the framework of low-energy effective field theory, as well as in the supersymmetric U(1) extension of the Standard Model with non-holomorphic soft terms and non-universal charges on the additional group.

In the first case, we calculate the contributions of New Physics vector operators to the amplitudes of b->svv transitions and give allowed regions for the corresponding Wilson coefficients compatible with current and future measurements in the Belle II experiment.

In the second case, the construction of a model with additional U(1) symmetry and its phenomenological applications are discussed. The Wilson coefficients are calculated, the allowed regions in the parameter space are found, and the prospects for detecting New Physics signals in the forthcoming Belle II and LHCb experiments are evaluated.

(Based on the materials of the candidate’s dissertation.)