The Standard Model does not explain neutrino masses, dark matter and the baryon
asymmetry of the Universe. To answer these open questions, we need to look for
answers in physics beyond the Standard Model. A natural way to extend the Stan-
dard Model is to add right-handed neutrinos, for which we can write a Majorana
mass term, and together with the left-handed neutrinos, a Dirac mass term. The
scotogenic model explains the smallness of neutrino masses as a quantum correction
at one-loop level and at the same time, it contains a dark matter candidate, which
can be either bosonic or fermionic. In the extended scotogenic model, two additional
hypothetical particles beyond the Standard Model are introduced to enable radia-
tive proton decay. In the Scotogenic model, it was shown that the observed baryon
asymmetry can be generated through leptogenesis, while in the extended scotogenic
model we only explore this possibility.
In the last part of the thesis, we show that the additional interactions in the
extended scotogenic model do not provide a new mechanism of generating the neu-
trino masses at one-loop level. We analyze the decay channels of the vector-like
quark D and the right-handed neutrino N . For the decay $D \to Q + \eta$, we calculate
the difference between the decay widths of the particle and antiparticle arising from
the interference between the tree-level amplitude and the amplitude of the quantum
correction. Finally, the possibility of generating baryon and lepton number asym-
metries in the extended scotogenic model is explored.
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