Particle-Antiparticle Mixing, CP Violation and Rare K and B Decays in a Minimal Theory of Fermion Masses

Understand

We present a detailed study of Delta F=2 observables and of rare K^+(K_L) and B_{s,d} meson decays in a "Minimal Theory of Fermion Masses" (MTFM).

• In this theory Yukawa couplings are generated through the mixing with heavy vectorlike (VF) fermions.
• This implies corrections to the SM quark couplings to W, Z and Higgs so that FCNC processes receive contributions from tree level Z and Higgs exchanges and W bosons couple to right-handed quarks.
• In a particular version of this model in which the Yukawa matrix lambda^D in the heavy down fermion sector is unitary, lambda^U =1 and M = M_{VF} is fixed, only three real and positive definite parameters describe New Physics (NP) contributions to all Delta F=2 and Delta F=1 observables in K and B_{s,d} systems once the known quark masses and the CKM matrix are correctly reproduced.