Octet dominance of nonleptonic hyperon decays in a nonrelativistic quark model

Extracting an effective Hamiltonian by taking the nonrelativistic limit of quark-quark scattering through $W$-boson exchange, it is shown that we obtain octet dominance for the matrix elements $〈B_s\left|H_W^{\mathrm{pc}}\right|B_r〉$ where $B_r$, $B_s$ denote ordinary baryons. Further, it is shown that the above matrix elements are enhanced so as to compensate the Cabibbo suppression factor $sin{\theta }_C$ to some extent.