Manifestation of a singlet heavy up-tupe quark in the branching ratios of rare decays $K\rightarrow\pi\nu\bar\nu$, $B\rightarrow\pi\nu\bar\nu$ and $B\rightarrow K\nu\bar\nu$
Abstract:
We investigate the implications of the model with a $SU(2)$-singlet up-type quark, heavy enough not to be produced at the LHC, namely, the contribution of the new quark to the branching ratios of the
$K\rightarrow\pi\nu\bar\nu$, $B\rightarrow\pi\nu\bar\nu$ and $B \rightarrow K\nu\bar\nu$ decays. We show that the deviation from the Standard Model can be up to $10\%$ in the case of a $5\rm\ TeV$ quark. Precise measurements of these branching ratios at the future experiments will allow to observe the contributions of the new quark or to impose stronger constraints on its mass.